{"title":"Australian Opals","description":null,"products":[{"product_id":"australian-opal-113ct-cabochon-andamooka-australia-ao009","title":"Australian Opal 11.3ct – Cabochon – Andamooka, Australia - AO009","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.2g = 11.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.1 x 1.3 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to changes in temperature and humidity, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in vast basins, for example, the Great Artesian Basin, an enormous underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional structure similar to a crystal. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make a fortune under extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a lively play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal Opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display brilliant colors as much as black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028008440133,"sku":"AO009","price":73.04,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33251-5_photoroom-025-20250319-094040.jpg?v=1779379098"},{"product_id":"australian-black-opal-03ct-cabochon-lightning-ridge-australia-ao016","title":"Australian Black Opal 0.3ct – Cabochon – Lightning Ridge, Australia - AO016","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.06g = 0.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.53 x 0.3 x 0.22 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases their resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out, making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play-of-color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the true boom began in the early 20th century when explorers discovered opal-bearing layers with striking color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, most famous for the deposits around Lightning Ridge. It possesses a dark body tone (black, gray, or dark blue) that intensifies the play-of-color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins in iron-rich sandstone or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark body tones and display vivid play-of-color similar to black opals. Crystal Opal Characterized by a translucent or transparent body tone. Sometimes in its rough state, it may show little color, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety possesses a white or milky-white body tone. It can display colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on their size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028009193797,"sku":"AO016","price":61.41,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41537_photoroom-001-20250402-005902.jpg?v=1779379113"},{"product_id":"australian-black-opal-055ct-cabochon-lightning-ridge-australia-ao025","title":"Australian black Opal 0.55ct – Cabochon – Lightning Ridge, Australia - AO025","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.11g = 0.55ct\u003c\/li\u003e\n\u003cli\u003eSize: 0.71 x 0.4 x 0.23 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the many types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for daily use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstone and clay, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play-of-color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for its so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a ridge during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous especially for the deposits around Lightning Ridge. It has a dark body tone (black, grey, or dark blue) which intensifies the play-of-color. Black opals often display the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstone or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and display vibrant play-of-color similar to black opals. Crystal Opal Characterized by a translucent or transparent body tone. Sometimes in its rough state, it may show little color, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white body tone. It can display colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on their size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028009390405,"sku":"AO025","price":180.98,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41564_photoroom-010-20250402-202523.jpg?v=1779379116"},{"product_id":"australian-black-opal-05ct-cabochon-lightning-ridge-australia-ao018","title":"Australian Black Opal 0.5ct – Cabochon – Lightning Ridge, Australia - AO018","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.1g = 0.5ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.6 x 0.34 x 0.27 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is mainly due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This arrangement creates the characteristic \"play-of-color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered layers containing opals with surprising color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous mainly for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play-of-color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Primarily extracted in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark hues and display vivid play-of-color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its raw state, it may show few colors, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can display colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028009521477,"sku":"AO018","price":87.26,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41543_photoroom-004-20250402-175359.jpg?v=1779379119"},{"product_id":"australian-opal-025ct-cabochon-lightning-ridge-australia-ao027","title":"Australian Opal 0.25ct – Cabochon – Lightning Ridge, Australia - AO027","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.05g = 0.25ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.51 x 0.31 x 0.29 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually seeps into tiny cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light hits the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a thunderstorm, struck by lightning. Reality or legend, this story has given the place a evocative and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous especially for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Primarily mined in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark hues and display vibrant plays of color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its rough state, it may show few colors, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can display colors as vibrant as black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028009652549,"sku":"AO027","price":61.41,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41570_photoroom-000-20250402-204945.jpg?v=1779379122"},{"product_id":"australian-opal-02ct-cabochon-lightning-ridge-australia-ao028","title":"Australian Opal 0.2ct - Cabochon - Lightning Ridge, Australia - AO028","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.04g = 0.2ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.5 x 0.33 x 0.2 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually seeps into tiny cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a crucial role: they arrange themselves in a regular three-dimensional crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for its so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous especially for the deposits around Lightning Ridge. It has a dark body tone (black, grey, or dark blue) which intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins found in iron-rich sandstone or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and display vibrant play of color similar to black opals. Crystal Opal Characterized by a translucent or transparent body tone. Sometimes in its raw state, it may show few colors, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white body tone. It can display colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gems in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028009816389,"sku":"AO028","price":42.01,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41573_photoroom-006-20250402-210827.jpg?v=1779379125"},{"product_id":"australian-opal-138ct-cabochon-andamooka-australia-ao049","title":"Australian Opal 13.8ct – Cabochon – Andamooka, Australia - AO049","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.7g = 13.8ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.7 x 1.6 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or dehydration, and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional structure similar to a crystal. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and difficult conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers in search of precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a lively play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it may appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky-white base. It can show colors as brilliant as black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those showing an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028009914693,"sku":"AO049","price":96.31,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43448_australian-opal-13-8ct---cabochon---andamooka--australia.jpg?v=1779379127"},{"product_id":"australian-black-opal-185ct-cabochon-lightning-ridge-australia-ao026","title":"Australian black Opal 1.85ct – Cabochon – Lightning Ridge, Australia - AO026","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.37g = 1.85ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.93 x 0.69 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most significant source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases their resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out, making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks like sandstone and clay, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Siliceous water gradually permeates small cracks and pores in the rock. When the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for its so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered layers containing opals with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story has given the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous primarily for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and violet. Boulder Opal Primarily mined in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and display vibrant play of color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its rough state, it may show little color, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can show colors as vivid as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010144069,"sku":"AO026","price":827.35,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41567_photoroom-011-20250402-202523.jpg?v=1779379129"},{"product_id":"australian-opal-135ct-cabochon-andamooka-australia-ao005","title":"Australian Opal 13.5ct – Cabochon – Andamooka, Australia - AO005","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.7g = 13.5ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.4 x 1.6 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most significant source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases their resistance to temperature and humidity variations, reducing the risk of cracking or drying out, and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that spans much of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located about 600 kilometers north of Adelaide. It is situated near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to strike it rich under extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, particularly famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often display the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a vibrant play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it may appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky-white base. It can show colors as brilliant as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety in which opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can fetch high values, especially those showing an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010209605,"sku":"AO005","price":87.91,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33239-5_photoroom-005-20250319-094040.jpg?v=1779379130"},{"product_id":"australian-opal-139ct-cabochon-andamooka-australia-ao062","title":"Australian Opal 13.9ct – Cabochon – Andamooka, Australia - AO062","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.7g = 13.9ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.2 x 1.9 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system extending over much of inland Australia. Silica-rich water gradually seeps into small cracks or pores in the rock. As this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light strikes it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers searching for precious opal veins and the chance to make a fortune under extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, famous especially for the Lightning Ridge deposit in New South Wales. It features a dark body tone (black, grey, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and violet. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and therefore show a vibrant play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white body tone. It can display brilliant colors as vibrant as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is incorporated into a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other locations. Value Andamooka opals are particularly appreciated for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010242373,"sku":"AO062","price":112.47,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/44975_photoroom-018-20250512-194716.jpg?v=1779379131"},{"product_id":"australian-opal-15ct-cabochon-andamooka-australia-ao054","title":"Australian Opal 15ct – Cabochon – Andamooka, Australia - AO054","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3g = 15ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2 x 1.6 x 0.6 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that spans much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. As this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular, crystal-like three-dimensional structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in the opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia, located approximately 600 kilometers north of Adelaide. It is situated near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It has a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus show a vivid play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate enhances the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which, after treatment, can resemble the rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can fetch high values, especially those showing an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010275141,"sku":"AO054","price":121.51,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43463_photoroom-008-20250512-180547.jpg?v=1779379131"},{"product_id":"australian-opal-155ct-cabochon-andamooka-australia-ao058","title":"Australian Opal 15.5ct – Cabochon – Andamooka, Australia - AO058","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3.1g = 15.5ct\u003c\/li\u003e\n\u003cli\u003eSize: 2.6 x 1.8 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the many varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases their resistance to temperature and humidity variations, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in vast basins, such as the Great Artesian Basin, an enormous underground water system spanning a large part of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. As this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It is situated near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and utilize manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking valuable opal veins and the chance to make a fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It has a dark base (black, grey, or dark blue) that enhances the play of color. Black opals often display the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus show a vibrant play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display brilliant colors similar to black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety in which opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively accessible prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010307909,"sku":"AO058","price":125.4,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/44963_photoroom-006-20250512-194716.jpg?v=1779379131"},{"product_id":"australian-opal-173ct-cabochon-andamooka-australia-ao055","title":"Australian Opal 17.3ct – Cabochon – Andamooka, Australia - AO055","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3.4g = 17.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.9 x 1.7 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to changes in temperature and humidity, reducing the risk of cracks or drying out, making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, such as the Great Artesian Basin, a vast underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular, three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in the opal when light strikes it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, famous especially for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often display the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder Opals can have darker tones and thus show a vibrant play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it may appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal Opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky-white base. It can display colors as brilliant as those of black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is particularly famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are primarily valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010438981,"sku":"AO055","price":139.62,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43466_photoroom-011-20250512-180547.jpg?v=1779379133"},{"product_id":"australian-opal-234ct-cabochon-andamooka-australia-ao056","title":"Australian Opal 23.4ct – Cabochon – Andamooka, Australia - AO056","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 4.6g = 23.4ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3 x 2.5 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or desiccation and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, such as the Great Artesian Basin, a vast underground water system that spans much of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. As this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when struck by light. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia, located approximately 600 kilometers north of Adelaide. It sits near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and therefore display a lively play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively accessible prices and rich color patterns. However, high-quality specimens can reach high values, especially those that show an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010504517,"sku":"AO056","price":189.39,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43469_photoroom-012-20250512-180547.jpg?v=1779379134"},{"product_id":"australian-opal-268ct-cabochon-andamooka-australia-ao010","title":"26.8ct Australian Opal – Cabochon – Andamooka, Australia - AO010","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 5.3g = 26.8ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.8 x 1.8 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates the small fissures or pores of the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and difficult conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a lively play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display brilliant colors as vibrant as those of black opals, but the light background tends to dampen the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety in which the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is particularly famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010602821,"sku":"AO010","price":190.67,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33254_australian-opal-26-8ct---cabochon---andamooka--australia.jpg?v=1779379135"},{"product_id":"australian-opal-301ct-cabochon-andamooka-australia-ao050","title":"Australian Opal 30.1ct – Cabochon – Andamooka, Australia - AO050","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 6g = 30.1ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.7 x 1.7 x 0.7 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of colour. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out and making them ideal for everyday use in jewellery. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that extends over a large part of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a crucial role: they arrange themselves in a regular three-dimensional crystal-like structure. This configuration creates the characteristic “play of colour,” the iridescent effect visible in opal when light hits it. The colour and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometres north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and difficult conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labour or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, famous especially for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play of colour. Black opals often show the most intense colour spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a lively play of colour similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colourless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colours as brilliant as black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colours can become much more intense as the dark substrate accentuates the opal's play of colour. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly appreciated for their relatively affordable prices and rich colour patterns. However, high-quality specimens can reach high values, especially those that show an intense play of colour or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010635589,"sku":"AO050","price":213.3,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43451_australian-opal-30-1ct---cabochon---andamooka--australia.jpg?v=1779379136"},{"product_id":"australian-opal-44ct-cabochon-andamooka-australia-ao060","title":"Australian Opal 4.4ct – Cabochon – Andamooka, Australia - AO060","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.8g = 4.4ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.6 x 1 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable compared to many opals from other locations. Their naturally lower water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out, and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that spans a large part of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This configuration creates the characteristic “play of color,” the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and difficult conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make a fortune under extreme conditions. Types of Australian Opal Black Opal – the rarest and most precious variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus show a vivid play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is most famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those showing an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010701125,"sku":"AO060","price":35.55,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/44969_photoroom-012-20250512-194716.jpg?v=1779379137"},{"product_id":"australian-opal-67ct-cabochon-andamooka-australia-ao053","title":"Australian Opal 6.7ct – Cabochon – Andamooka, Australia - AO053","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.3g = 6.7ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.8 x 1.4 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are noticeably more durable and stable than many opals from other locations. Their lower natural water content increases resistance to variations in temperature and humidity, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, such as the Great Artesian Basin, a vast underground water system extending over much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to strike it rich in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, famous especially for the Lightning Ridge deposit in New South Wales. It has a dark base (black, gray, or dark blue) which enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and therefore display a lively play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can show colors as brilliant as black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those showing an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010733893,"sku":"AO053","price":54.3,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43460_photoroom-006-20250512-180547.jpg?v=1779379138"},{"product_id":"boulder-opal-132ct-cabochon-koroit-queensland-australia-bo023","title":"Boulder opal 13.2ct – Cabochon – Koroit, Queensland, Australia - BO023","description":"\u003cul\u003e\n\u003cli\u003eLocation: Koroit, Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.6g = 13.2ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.4 x 1.4 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia offers—from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are notably more durable and stable compared to many Opals from Other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian Opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into Opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in Opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder Opals from Australia’s Queensland, the fundamental formation process is the same, but the Opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the Opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder Opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant Opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian Opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve Opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of Opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black Opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when Opal fills thin seams in ironstone or Other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder Opals can have a darker body tone, and thus can—like black Opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal Opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black Opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White Opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder Opals.\nMatrix Opal A distinct variety in which Opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the Opal’s play of color. Andamooka is especially famous for this type of matrix Opal, known as Andamooka Matrix, which can resemble rare black Opals from Other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010832197,"sku":"BO023","price":113.12,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43037_boulder-opal-13-2ct---cabochon---koroit--queensland--australia.jpg?v=1779379139"},{"product_id":"boulder-opal-17ct-cabochon-queensland-australia-bo013","title":"Boulder opal 1.7ct – Cabochon – Queensland, Australia - BO013","description":"\u003cul\u003e\n\u003cli\u003eLocation: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.34g = 1.7ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.84 x 0.6 x 0.28 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia offers—from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are notably more durable and stable compared to many Opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian Opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into Opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in Opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder Opals from Australia’s Queensland, the fundamental formation process is the same, but the Opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the Opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder Opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant Opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian Opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve Opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack OpalThe rarest and most valuable type of Opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black Opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when Opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder Opals can have a darker body tone, and thus can—like black Opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal Opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black Opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White Opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder Opals.\nMatrix OpalA distinct variety in which Opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the Opal’s play of color. Andamooka is especially famous for this type of matrix Opal, known as Andamooka Matrix, which can resemble rare black Opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010864965,"sku":"BO013","price":216.53,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41531_photoroom-001-20250402-002040.jpg?v=1779379141"},{"product_id":"australian-opal-332ct-cabochon-andamooka-australia-ao002","title":"Australian Opal 33.2ct – Cabochon – Andamooka, Australia - AO002","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 6.6g = 33.2ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3 x 2.5 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-colour. Thanks to specific formation conditions, they often exhibit vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases their resistance to temperature and humidity variations, reducing the risk of cracking or drying out, making them ideal for everyday use in jewellery. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system extending over much of inland Australia. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional structure similar to a crystal. This configuration creates the characteristic \"play-of-colour,\" the iridescent effect visible in opal when light hits it. The colour and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometres north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterised by an arid climate and difficult conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labour or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking valuable opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, famous especially for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play-of-colour. Black opals often show the most intense colour spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus show a vibrant play-of-colour similar to black opals. Crystal Opal – characterised by a transparent or translucent base. In its rough state, it can appear almost colourless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky-white base. It can show colours as brilliant as black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colours can become much more intense as the dark substrate accentuates the opal's play-of-colour. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which, after treatment, can resemble the rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich colour patterns. However, high-quality specimens can fetch high values, especially those that exhibit an intense play-of-colour or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010930501,"sku":"AO002","price":215.24,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33230-5_australian-opal-33-2ct---cabochon---andamooka--australia.jpg?v=1779379141"},{"product_id":"boulder-opal-1865ct-cabochon-koroit-queensland-australia-bo021","title":"Boulder Opal 18.65ct – Cabochon – Koroit, Queensland, Australia - BO021","description":"\u003cul\u003e\n\u003cli\u003eLocation: Koroit, Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3.7g = 18.65ct\u003c\/li\u003e\n\u003cli\u003eSize: 2.3 x 1.5 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of opals Australia offers—from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder opals from Australia’s Queensland, the fundamental formation process is the same, but the opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder opals can have a darker body tone, and thus can—like black opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder opals.\nMatrix Opal A distinct variety in which opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the opal’s play of color. Andamooka is especially famous for this type of matrix opal, known as Andamooka Matrix, which can resemble rare black opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028010963269,"sku":"BO021","price":128.63,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43031_boulder-opal-18-65ct---cabochon---koroit--queensland--australia.jpg?v=1779379142"},{"product_id":"boulder-opal-185ct-cabochon-queensland-australia-bo008","title":"Boulder opal 18.5ct – Cabochon – Queensland, Australia - BO008","description":"\u003cul\u003e\n\u003cli\u003eLocation: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3.7g = 18.5ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.6 x 1.8 x 0.7 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia offers—from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are notably more durable and stable compared to many Opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian Opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into Opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in Opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder Opals from Australia’s Queensland, the fundamental formation process is the same, but the Opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the Opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder Opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant Opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian Opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve Opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack OpalThe rarest and most valuable type of Opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black Opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when Opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder Opals can have a darker body tone, and thus can—like black Opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal Opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black Opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White Opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder Opals.\nMatrix OpalA distinct variety in which Opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the Opal’s play of color. Andamooka is especially famous for this type of matrix Opal, known as Andamooka Matrix, which can resemble rare black Opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028011028805,"sku":"BO008","price":96.31,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/6447_boulder-opal-18-5ct---cabochon---queensland--australia.jpg?v=1779379144"},{"product_id":"boulder-opal-223ct-cabochon-queensland-australia-bo002","title":"Boulder Opal 22.3ct – Cabochon – Queensland, Australia - BO002","description":"\u003cul\u003e\n\u003cli\u003eLocation: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 4.4g = 22.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.6 x 1.9 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of opals Australia offers—from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder opals from Australia’s Queensland, the fundamental formation process is the same, but the opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder opals can have a darker body tone, and thus can—like black opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder opals.\nMatrix Opal A distinct variety in which opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the opal’s play of color. Andamooka is especially famous for this type of matrix opal, known as Andamooka Matrix, which can resemble rare black opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028011094341,"sku":"BO002","price":232.05,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/6429_boulder-opal-22-3ct---cabochon---queensland--australia.jpg?v=1779379144"},{"product_id":"boulder-opal-22ct-cabochon-queensland-australia-bo004","title":"Boulder opal 22ct – Cabochon – Queensland, Australia - BO004","description":"\u003cul\u003e\n\u003cli\u003eLocation: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 4.4g = 22ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.3 x 1.2 x 0.6 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia offers—from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are notably more durable and stable compared to many Opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian Opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into Opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in Opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder Opals from Australia’s Queensland, the fundamental formation process is the same, but the Opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the Opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder Opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant Opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian Opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve Opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack OpalThe rarest and most valuable type of Opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black Opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when Opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder Opals can have a darker body tone, and thus can—like black Opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal Opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black Opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White Opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder Opals.\nMatrix OpalA distinct variety in which Opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the Opal’s play of color. Andamooka is especially famous for this type of matrix Opal, known as Andamooka Matrix, which can resemble rare black Opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028011258181,"sku":"BO004","price":154.48,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/6435_boulder-opal-22ct---cabochon---queensland--australia.jpg?v=1779379149"},{"product_id":"australian-opal-705ct-cabochon-andamooka-australia-ao046","title":"Australian Opal 7.05ct – Cabochon – Andamooka, Australia - AO046","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.4g = 7.05ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.6 x 0.9 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opals are renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other locations. Their lower natural water content increases their resistance to temperature and humidity variations, reducing the risk of cracks or drying out, making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system extending over much of the Australian interior. Siliceous water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in the opal when struck by light. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It has a dark base (black, grey, or dark blue) that enhances the play of color. Black opals often display the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus show a lively play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it may appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky-white base. It can show colors as bright as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which, after treatment, can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can fetch high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028109693253,"sku":"AO046","price":49.77,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43439_australian-opal-7-05ct---cabochon---andamooka--australia.jpg?v=1779380286"},{"product_id":"boulder-opal-14ct-cabochon-queensland-australia-bo012","title":"Boulder Opal 1.4ct – Cabochon – Queensland, Australia - BO012","description":"\u003cul\u003e\n\u003cli\u003eLocation: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.28g = 1.4ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.94 x 0.57 x 0.28 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of opals Australia offers—from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder opals from Australia’s Queensland, the fundamental formation process is the same, but the opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder opals can have a darker body tone, and thus can—like black opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder opals.\nMatrix Opal A distinct variety in which opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the opal’s play of color. Andamooka is especially famous for this type of matrix opal, known as Andamooka Matrix, which can resemble rare black opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028111429957,"sku":"BO012","price":297.32,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/6459_photoroom-002-20250402-210827.jpg?v=1779380292"},{"product_id":"australian-black-opal-025ct-cabochon-lightning-ridge-australia-ao024","title":"Australian Black Opal 0.25ct – Cabochon – Lightning Ridge, Australia - AO024","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.05g = 0.25ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.5 x 0.33 x 0.21 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the many types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually penetrates tiny cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with striking color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, especially famous for the deposits around Lightning Ridge. It has a dark body tone (black, grey, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Primarily mined in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting backing. Boulder opals can have dark hues and display vibrant plays of color similar to black opals. Crystal Opal Characterized by a translucent or transparent body tone. Sometimes in its rough state, it may show little color, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white body tone. It can display colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118212933,"sku":"AO024","price":54.95,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41561_photoroom-024-20250402-194152.jpg?v=1779380397"},{"product_id":"australian-black-opal-03ct-cabochon-lightning-ridge-australia-ao019","title":"Australian black Opal 0.3ct – Cabochon – Lightning Ridge, Australia - AO019","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.06g = 0.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.5 x 0.32 x 0.21 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the many types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually seeps into small cracks and porosities in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with striking color effects. The name \"Lightning Ridge\" is linked to a legend according to which a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, primarily famous for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins found in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and display vibrant plays of color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its rough state, it may show few colors, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can show colors as vivid as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or many bright hues, are considered among the most expensive gems in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118245701,"sku":"AO019","price":51.06,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41546_photoroom-002-20250402-175359.jpg?v=1779380400"},{"product_id":"australian-black-opal-035ct-cabochon-lightning-ridge-australia-ao021","title":"Australian black Opal 0.35ct – Cabochon – Lightning Ridge, Australia - AO021","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.07g = 0.35ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.56 x 0.33 x 0.22 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia—from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases their resistance to temperature fluctuations and humidity changes, reducing the risk of cracks or drying out, making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Water rich in silica gradually penetrates tiny cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a crucial role: they arrange themselves in a regular three-dimensional crystal-like structure. This arrangement creates the characteristic \"play-of-color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for its so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a thunderstorm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, primarily famous for the deposits around Lightning Ridge. It possesses a dark body tone (black, grey, or dark blue) which intensifies the play-of-color. Black opals often display the most intense color range, including red, green, blue, and purple. Boulder Opal Mined mainly in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and exhibit vibrant play-of-color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its raw state, it may show little color, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety possesses a white or milky-white base. It can display colors as vivid as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is embedded within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gems in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118311237,"sku":"AO021","price":61.41,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41552_photoroom-005-20250402-182737.jpg?v=1779380401"},{"product_id":"australian-opal-103ct-cabochon-andamooka-australia-ao052","title":"Australian Opal 10.3ct – Cabochon – Andamooka, Australia - AO052","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2g = 10.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2 x 1.5 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in vast basins, for example, the Great Artesian Basin, a massive underground water system extending over much of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic “play of color,” the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia’s oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a vivid play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it may appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal’s play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118638917,"sku":"AO052","price":87.26,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43457_australian-opal-10-3ct---cabochon---andamooka--australia.jpg?v=1779380406"},{"product_id":"australian-opal-27ct-cabochon-lightning-ridge-australia-ao012","title":"Australian Opal 2.7ct – Cabochon – Lightning Ridge, Australia - AO012","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.54g = 2.7 ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.3 x 1 x 0.2 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is world-renowned as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstone and clay, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves into a regular three-dimensional crystal-like structure. This arrangement creates the characteristic “play of color,” the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most precious varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with striking color effects. The name “Lightning Ridge” is linked to a legend that a shepherd and his flock died on a ridge during a thunderstorm, struck by lightning. Reality or legend, this story has given the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, particularly famous for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins in iron-rich sandstone or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark hues and display vibrant plays of color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its raw state, it may show few colors, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal This variety has a white or milky-white base. It can show colors as vibrant as black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and clarity of the stone. The rarest specimens, especially those with a predominance of red or many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118671685,"sku":"AO012","price":898.45,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41525_photoroom-000-20250401-234729.jpg?v=1779380411"},{"product_id":"australian-opal-075ct-cabochon-lightning-ridge-australia-ao013","title":"Australian Opal 0.75ct – Cabochon – Lightning Ridge, Australia - AO013","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.15g = 0.75ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.76 x 0.55 x 0.14 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opals are renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstone and clay, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Siliceous water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic “play of color,” the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most precious varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name “Lightning Ridge” is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a evocative and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous primarily for the deposits around Lightning Ridge. It has a dark base (black, grey, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Extracted mainly in northeastern Queensland. It forms when opal fills thin veins in iron-rich sandstone or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark hues and display vivid plays of color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its rough state, it may show few colors, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations such as Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can show colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118737221,"sku":"AO013","price":252.09,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41528_australian-opal-0-75ct---cabochon--lightning-ridge--australia.jpg?v=1779380411"},{"product_id":"australian-opal-231ct-cabochon-andamooka-australia-ao045","title":"Australian Opal 23.1ct – Cabochon – Andamooka, Australia - AO045","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 4.6g = 23.1ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.1 x 2.2 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular, three-dimensional, crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when struck by light. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located about 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make a fortune under extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder Opals can have darker tones and therefore show a vivid play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it may appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal Opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that show an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118769989,"sku":"AO045","price":226.23,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43436_australian-opal-23-1ct---cabochon---andamooka--australia.jpg?v=1779380411"},{"product_id":"australian-opal-108ct-cabochon-andamooka-australia-ao004","title":"Australian Opal 10.8ct – Cabochon – Andamooka, Australia - AO004","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.1g = 10.8ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.2 x 1.6 x 0.3 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the many varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their lower natural water content increases their resistance to variations in temperature and humidity, reducing the risk of cracks or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstone and clay found in vast basins, for example the Great Artesian Basin, an enormous underground water system that extends over much of the Australian interior. Siliceous water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional structure similar to a crystal. This configuration creates the characteristic \"play-of-color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and difficult conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make a fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most precious variety, famous above all for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play-of-color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder Opals can have darker tones and therefore display a vivid play-of-color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal Opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play-of-color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other locations. Value Andamooka opals are prized primarily for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play-of-color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118835525,"sku":"AO004","price":69.81,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33236-5_photoroom-000-20250319-094040.jpg?v=1779380412"},{"product_id":"australian-opal-05ct-cabochon-lightning-ridge-australia-ao023","title":"Australian Opal 0.5ct – Cabochon – Lightning Ridge, Australia - AO023","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.1g = 0.5ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.7 x 0.41 x 0.21 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases their resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of inland Australia). Silica-rich water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play-of-color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal deposit located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered layers containing opals with surprising color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story has given the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous primarily for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play-of-color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and display vivid play-of-color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its rough state, it may show few colors, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can display colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118901061,"sku":"AO023","price":219.77,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41558_photoroom-020-20250402-194152.jpg?v=1779380414"},{"product_id":"australian-opal-215ct-cabochon-andamooka-australia-ao006","title":"Australian Opal 21.5ct – Cabochon – Andamooka, Australia - AO006","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 4.3g = 21.5ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3 x 1.8 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and highly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases their resistance to temperature and humidity variations, reducing the risk of cracks or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in vast basins, for example, the Great Artesian Basin, a massive underground water system extending over much of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a vivid play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to attenuate the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly appreciated for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that show an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118933829,"sku":"AO006","price":138.97,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33242-5_photoroom-010-20250319-094040.jpg?v=1779380415"},{"product_id":"australian-opal-83ct-cabochon-andamooka-australia-ao043","title":"Australian opal 8.3ct – Cabochon – Andamooka, Australia - AO043","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.6g = 8.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.2 x 1.2 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out, making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, such as the Great Artesian Basin, a vast underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular, three-dimensional, crystal-like structure. This configuration creates the characteristic “play of color,” the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian opal Black Opal – the rarest and most precious variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a lively play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its rough state, it may appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can fetch high values, especially those showing an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028118999365,"sku":"AO043","price":61.41,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43430_australian-opal-8-3ct---cabochon---andamooka--australia.jpg?v=1779380415"},{"product_id":"australian-opal-227ct-cabochon-andamooka-australia-ao008","title":"Australian Opal 22.7ct – Cabochon – Andamooka, Australia - AO008","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 4.5g = 22.7ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.2 x 1.4 x 0.6 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that extends over much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when struck by light. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking precious opal veins and the chance to make their fortune in extreme conditions. Types of Australian Opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, grey, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a lively play of color similar to that of black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as those of black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028119097669,"sku":"AO008","price":146.73,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33248-5_photoroom-020-20250319-094040.jpg?v=1779380416"},{"product_id":"australian-opal-93ct-cabochon-andamooka-australia-ao044","title":"Australian Opal 9.3ct – Cabochon – Andamooka, Australia - AO044","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.8g = 9.3ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2 x 1.8 x 0.3 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the many varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracking or drying out, and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks such as sandstones and clays found in enormous basins, for example, the Great Artesian Basin, a vast underground water system that spans a large part of the Australian interior. Silica-rich water gradually penetrates small fissures or pores in the rock. As this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular, crystal-like three-dimensional structure. This configuration creates the characteristic \"play of color,\" the iridescent effect visible in opal when struck by light. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and challenging conditions. However, rich opal veins were discovered here in the 1930s, making Andamooka one of Australia's oldest opal mining fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking valuable opal veins and the chance to strike it rich under extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, especially famous for the Lightning Ridge deposit in New South Wales. It features a dark base (black, gray, or dark blue) that enhances the play of color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – mainly extracted in Queensland. It forms when opal fills thin veins in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a vibrant play of color similar to black opals. Crystal Opal – characterized by a transparent or translucent base. In its raw state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky white base. It can display colors as brilliant as black opals, but the light background tends to diminish the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is embedded in a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play of color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can reach high values, especially those that display an intense play of color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028119064901,"sku":"AO044","price":63.99,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43433_australian-opal-9-3ct---cabochon---andamooka--australia.jpg?v=1779380416"},{"product_id":"boulder-opal-158ct-cabochon-koroit-queensland-australia-bo022","title":"Boulder opal 15.8ct – Cabochon – Koroit, Queensland, Australia - BO022","description":"\u003cul\u003e\n\u003cli\u003eLocation: Koroit, Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3.1g = 15.8ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.9 x 1.3 x 0.6 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of opals Australia offers—from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder opals from Australia’s Queensland, the fundamental formation process is the same, but the opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian opals\nBlack Opal The rarest and most valuable type of opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder opals can have a darker body tone, and thus can—like black opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder opals.\nMatrix Opal A distinct variety in which opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the opal’s play of color. Andamooka is especially famous for this type of matrix opal, known as Andamooka Matrix, which can resemble rare black opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028119294277,"sku":"BO022","price":113.12,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43034_boulder-opal-15-8ct---cabochon---koroit--queensland--australia.jpg?v=1779380419"},{"product_id":"australian-opal-88ct-cabochon-andamooka-australia-ao007","title":"Australian Opal 8.8ct – Cabochon – Andamooka, Australia - AO007","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.7g = 8.8ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.5 x 1.3 x 0.3 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vibrant and strongly contrasting hues. This diversity is reflected in the numerous varieties of opals offered by Australia: from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their lower natural water content increases resistance to temperature and humidity variations, reducing the risk of cracks or drying out, and making them ideal for everyday use in jewelry. Formation Australian opals generally form in sedimentary rocks like sandstones and clays found in vast basins, such as the Great Artesian Basin, an immense underground water system spanning much of the Australian interior. Silica-rich water gradually penetrates small cracks or pores in the rock. When this water evaporates or drains away, thin layers of silica remain in the cavities and can slowly transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This configuration creates the characteristic \"play-of-color,\" the iridescent effect visible in opal when light hits it. The color and intensity of this effect depend on the size and arrangement of these spheres. Deposits Andamooka is a small mining town in South Australia, located approximately 600 kilometers north of Adelaide. It lies near the salt lake Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. However, in the 1930s, rich opal veins were discovered here, making Andamooka one of Australia's oldest opal fields. History Although Andamooka is not as famous as Coober Pedy or Lightning Ridge, opal mining here has a long tradition. Many mines are still family-run and use manual labor or small machinery. In the past, Andamooka, like other Australian mining fields, attracted adventurers seeking valuable opal veins and the chance to strike it rich under extreme conditions. Types of Australian opal Black Opal – the rarest and most valuable variety, particularly famous for the Lightning Ridge deposit in New South Wales. It features a dark body tone (black, grey, or dark blue) that enhances the play-of-color. Black opals often show the most intense color spectrum, including red, green, blue, and purple. Boulder Opal – primarily mined in Queensland. It forms when opal fills thin veins in iron-rich sandstone or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have darker tones and thus display a vivid play-of-color similar to black opals. Crystal Opal – characterized by a transparent or translucent body tone. In its rough state, it can appear almost colorless, but the iridescence becomes evident through a crystalline or milky base. Crystal Opals are found throughout Australia, with larger quantities coming from Coober Pedy. White Opal (Light Opal) – this variety has a white or milky-white body tone. It can display colors as brilliant as black opals, but the light background tends to soften the visual contrast, making the effect less intense. White opals are particularly common in Coober Pedy and generally more accessible than black or boulder opals. Matrix Opal – a particular variety where the opal is incorporated into a porous rock, such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense as the dark substrate accentuates the opal's play-of-color. Andamooka is especially famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble rare black opals from other locations. Value Andamooka opals are particularly valued for their relatively affordable prices and rich color patterns. However, high-quality specimens can fetch high values, especially those showing an intense play-of-color or particularly spectacular patterns, such as the harlequin pattern.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028119359813,"sku":"AO007","price":56.88,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/33245-5_photoroom-015-20250319-094040.jpg?v=1779380421"},{"product_id":"australian-opal-22ct-cabochon-lightning-ridge-australia-ao022","title":"Australian Opal 2.2ct – Cabochon – Lightning Ridge, Australia - AO022","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.44g = 2.2ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.23 x 1 x 0.21 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the many types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks such as sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Siliceous water gradually penetrates tiny cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for so-called black opals, considered among the rarest and most precious varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Fact or legend, this story gave the place a evocative and memorable name. Types of Australian Opals Black Opal The rarest and most precious type of opal, especially famous for the deposits around Lightning Ridge. It has a dark base (black, grey, or dark blue) which intensifies the play of color. Black opals often display the most intense color range, including red, green, blue, and purple. Boulder Opal Mainly extracted in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and show vibrant plays of color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its raw state, it may show few colors, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can show colors as vibrant as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where the opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028119621957,"sku":"AO022","price":504.17,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41555_photoroom-000-20250402-194554.jpg?v=1779380424"},{"product_id":"boulder-opal-78ct-cabochon-winton-queensland-australia-bo014","title":"Boulder opal 7.8ct – Cabochon – Winton, Queensland, Australia - BO014","description":"\u003cul\u003e\n\u003cli\u003eLocation: Winton, Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.56g = 7.8ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.74 x 1 x 0.36 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals lies primarily in their striking and pure play of color. Thanks to the specific conditions in which they form, they often feature vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia has to offer—ranging from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are also notably more durable and stable compared to many others. Their naturally lower water content increases their resilience to temperature fluctuations and changes in humidity, so they do not crack or dry out as easily, making them ideal for everyday jewelry wear.\nFormation\nAustralian Opals typically form in sedimentary rocks such as sandstone and clay, which occur in expansive basins (for example, the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Silica-rich water slowly seeps into fine cracks or pores in the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually form Opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular, three-dimensional “crystal-like” grid. This arrangement produces the typical “play-of-color” phenomenon—an iridescent display visible in Opal when light hits it. The color and intensity of this effect depend on the size and distribution of these spheres.\nIn the case of boulder Opals from Queensland in Australia (for example, around Winton), the basic formation process is the same, except the Opal is deposited in thin seams or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and intensity of the Opal’s color play.\nDeposits\nWinton is a small town in northwestern Queensland, Australia, located roughly 177 kilometers northwest of Longreach. This area is especially renowned for boulder Opals, which occur in abundant veins within iron-rich sandstones. Winton’s dry, semi-desert climate, combined with its geological conditions, greatly contributes to both the formation and preservation of Opals.\nHistory\nBoulder Opal mining in Winton began around the turn of the 19th and 20th centuries, similar to other key Opal-mining regions in Australia (Lightning Ridge, Quilpie, Opalton, etc.). Because it is more difficult to extract Opal from the hard host rock, early mining operations were often small-scale private ventures. Modern mining now uses some mechanization, yet many independent prospectors and family-run operations still work the mines by hand.\nTypes of Australian Opals\nBlack Opal (Black Opal) The rarest and most valuable type of Opal, best known from deposits in Lightning Ridge (New South Wales). It has a dark base color (black, gray, or dark blue) that enhances the play of color. Black Opals often display the most intense color range—including red, green, blue, and purple.\nBoulder Opal Mainly mined in Queensland (northeastern Australia). It forms when Opal fills thin seams in iron-rich sandstone or other types of parent rock (“boulder”). This variety typically retains part of the original rock, creating a contrasting backdrop. Boulder Opals can have a darker body tone and, like black Opals, exhibit a vivid play of color.\nCrystal Opal Characterized by a translucent or transparent base. At times it may appear nearly colorless in its rough state, yet the rainbow-like flashes shine clearly through the crystal-clear or milky, translucent body. Crystal Opals are found throughout Australia, but larger quantities come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display colors just as vibrant as those in black Opals, but they tend to appear less intense because the light background visually “mutes” the contrast. White Opal is especially common in Coober Pedy (South Australia) and is more affordable than black or boulder Opals.\nMatrix Opal A distinctive variety in which Opal is embedded in porous rock (e.g., sandstone or ironstone). After treatment (impregnation), the colors can become significantly more intense, because the darker base accentuates the Opal’s play of color. Andamooka is particularly famous for these matrix Opals, known as Andamooka Matrix, which can resemble rare black Opals from other regions once processed.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028168872261,"sku":"BO014","price":248.85,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41669_photoroom-000-20250402-210927.jpg?v=1779381357"},{"product_id":"australian-opal-185ct-cabochon-andamooka-australia-ao047","title":"18.5ct Australian Opal – Cabochon – Andamooka, Australia - AO047","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 3.7g = 18.5ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.1 x 1.9 x 0.4 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia offers—from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are notably more durable and stable compared to many Opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian Opals typically form in sedimentary rocks, such as sandstones and clays, found in vast basins (for instance, the Great Artesian Basin—a massive underground water system spanning much of Australia’s interior). Silica-rich water gradually seeps into fine cracks or pores within these rocks. When this water evaporates or otherwise drains away, thin layers of silica remain in the cavities, which can eventually develop into Opal.\nMicroscopic spheres of silicon dioxide (silica) play a key role: they arrange themselves into a regular three-dimensional “crystal-like” lattice. This structure creates the characteristic “play-of-color,” the iridescent effect visible in Opal when light strikes it. The color and intensity of this effect depend on the size and arrangement of these spheres.\nDeposits\nAndamooka is a small mining town in South Australia, located about 600 kilometers north of Adelaide. It lies near the salt lake known as Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. Nevertheless, in the 1930s, rich Opal veins were discovered here, making Andamooka one of the oldest Opal mining fields in Australia.\nHistory\nThough Andamooka is not as famous as Coober Pedy or Lightning Ridge, Opal mining here has a long-standing tradition. Many of the mines remain family-run operations, often employing manual labor or small-scale machinery. In the past, Andamooka—like other Australian Opal fields—drew adventurers seeking valuable Opal seams in these tough conditions, hoping to discover a profitable find.\nTypes of Australian Opals\nBlack Opal (Black Opal) The rarest and most valuable type of Opal, renowned especially for the Lightning Ridge deposit in New South Wales. It has a dark body color (black, gray, or dark blue), which enhances the play of color. Black Opals often exhibit the most intense color spectrum—including red, green, blue, and purple.\nBoulder Opal Primarily mined in Queensland (northeastern Australia). It forms when Opal fills thin veins in iron-rich sandstone or other types of host rock (“boulder”). This variety usually retains part of the original rock, creating a contrasting base. Boulder Opals can have a darker tone, and therefore—similar to black Opals—feature a vivid play of color.\nCrystal Opal Characterized by a translucent or transparent background. In its rough state, it can sometimes appear nearly colorless, yet the iridescent flashes become apparent through a crystal-clear or milky base. Crystal Opals are found across Australia, with larger quantities coming from Coober Pedy.\nWhite (Light) Opal This type has a white or milky-white base color. It can exhibit colors as bright as those of black Opals, though the light background often “mutes” the contrast, resulting in a less intense effect. White Opal is especially common in Coober Pedy (South Australia) and is generally more affordable than black or boulder Opals.\nMatrix Opal A special variety in which Opal is embedded within a porous host rock (e.g., sandstone or ironstone). After treatment (impregnation), the colors can become much more vibrant, as the darker substrate intensifies the Opal’s play-of-color. Andamooka is chiefly known for these matrix Opals—referred to as Andamooka Matrix—which, once treated, can resemble rare black Opals from other localities.\nValue Opals from Andamooka are popular mainly for their relatively accessible prices and richly colored patterns. Nevertheless, high-quality pieces can still command substantial sums, especially those displaying intense color play or striking patterns (like a harlequin pattern).\nAustralian Opal – cabochon – Andamooka, Australia\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028174573893,"sku":"AO047","price":128.63,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43442_australian-opal-18-5ct---cabochon---andamooka--australia.jpg?v=1779381484"},{"product_id":"australian-opal-04ct-cabochon-lightning-ridge-australia-ao020","title":"Australian Opal 0.4ct – Cabochon – Lightning Ridge, Australia - AO020","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.08g = 0.4ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.68 x 0.63 x 0.15 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play-of-color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are significantly more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks like sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually seeps into small cracks and porosities in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional crystal-like structure. This arrangement creates the characteristic \"play-of-color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal deposit located in the Australian state of New South Wales, approximately 770 kilometers northwest of Sydney. This area is particularly famous for its black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered layers containing opals with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a suggestive and memorable name. Types of Australian Opals Black Opal The rarest and most precious type of opal, especially famous for the deposits around Lightning Ridge. It has a dark base (black, gray, or dark blue) that intensifies the play-of-color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark tones and exhibit vivid play-of-color similar to black opals. Crystal Opal Characterized by a translucent or transparent base. Sometimes in its rough state, it may show few colors, but once cut, it reveals prismatic flashes through a clear or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white base. It can display colors as vivid as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and purity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gemstones in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028174606661,"sku":"AO020","price":862.89,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41549_photoroom-002-20250402-182737.jpg?v=1779381484"},{"product_id":"australian-opal-057ct-cabochon-lightning-ridge-australia-ao017","title":"Australian Opal 0.57ct – Cabochon – Lightning Ridge, Australia - AO017","description":"\u003cul\u003e\n\u003cli\u003eLocation: Lightning Ridge, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 0.114g = 0.57ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 0.83 x 0.5 x 0.2 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralian Opal is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their intense and pure play of color. Thanks to specific formation conditions, they often display vivid and contrasting hues. This variety is reflected in the numerous types of opal found in Australia — from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable than many opals from other locations. Their naturally lower water content increases resistance to temperature fluctuations and humidity changes, reducing the risk of cracking or drying out and making them ideal for everyday use in jewelry. Formation Australian opals typically form in sedimentary rocks like sandstones and clays, found in large geological basins (e.g., the Great Artesian Basin, a vast underground water system covering much of Australia's interior). Silica-rich water gradually penetrates small cracks and pores in the rock. As the water evaporates or drains away, thin layers of silica remain in the cavities and can transform into opal. Microscopic spheres of silicon dioxide (silica) play a fundamental role: they arrange themselves in a regular three-dimensional, crystal-like structure. This arrangement creates the characteristic \"play of color,\" the iridescent effect visible when light strikes the opal. The color and intensity of this effect depend on the size and arrangement of the spheres. Deposits Lightning Ridge is a legendary opal field located in the Australian state of New South Wales, about 770 kilometers northwest of Sydney. This area is particularly famous for the so-called black opals, considered among the rarest and most valuable varieties in the world. History Mining activity in this area dates back to the late 19th century, but the real boom began in the early 20th century when explorers discovered opal-bearing layers with astonishing color effects. The name \"Lightning Ridge\" is linked to a legend that a shepherd and his flock died on a hill during a storm, struck by lightning. Reality or legend, this story gave the place a evocative and memorable name. Types of Australian Opals Black Opal The rarest and most valuable type of opal, famous primarily for the deposits around Lightning Ridge. It has a dark body tone (black, grey, or dark blue) that intensifies the play of color. Black opals often show the most intense color range, including red, green, blue, and purple. Boulder Opal Mined primarily in northeastern Queensland. It forms when opal fills thin veins present in iron-rich sandstones or other host rocks. This variety often retains part of the original rock, creating a contrasting base. Boulder opals can have dark hues and display vivid play of color similar to black opals. Crystal Opal Characterized by a translucent or transparent body tone. Sometimes in its raw state, it may show few colors, but once cut, it reveals prismatic flashes through a transparent or milky background. Crystal opals are found throughout Australia, with significant quantities coming from locations like Coober Pedy. White Opal (Light Opal) This variety has a white or milky-white body tone. It can show colors as vivid as those of black opals, but they generally appear less intense because the light background reduces visual contrast. White opals are particularly common in Coober Pedy and are more accessible than black or boulder opals. Matrix Opal A special variety where opal is found within porous rocks such as sandstone or ironstone. After impregnation treatments, the colors can become much more intense due to the contrast created by the dark matrix. Andamooka is famous for these matrix opals, called Andamooka Matrix, which after treatment can resemble the rare black opals from other areas. Value The prices of black opals from Lightning Ridge can reach astronomical figures, depending on the size, saturation, variety of colors, pattern arrangement, and clarity of the stone. The rarest specimens, especially those with a predominance of red or with many bright hues, are considered among the most expensive gems in the world.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028174639429,"sku":"AO017","price":639.9,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/41540_photoroom-20250402-175542.jpg?v=1779381487"},{"product_id":"australian-opal-74ct-cabochon-andamooka-australia-ao059","title":"Australian Opal 7.4ct – Cabochon – Andamooka, Australia - AO059","description":"\u003cul\u003e\n\u003cli\u003eLocation: Andamooka, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 1.4g = 7.4ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 2.5 x 1.2 x 0.3 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opals. The quality of Australian Opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of Opals Australia offers—from black and boulder Opals to crystal, white, and matrix Opals. Australian Opals are notably more durable and stable compared to many Opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian Opals typically form in sedimentary rocks, such as sandstones and clays, found in vast basins (for instance, the Great Artesian Basin—a massive underground water system spanning much of Australia’s interior). Silica-rich water gradually seeps into fine cracks or pores within these rocks. When this water evaporates or otherwise drains away, thin layers of silica remain in the cavities, which can eventually develop into Opal.\nMicroscopic spheres of silicon dioxide (silica) play a key role: they arrange themselves into a regular three-dimensional “crystal-like” lattice. This structure creates the characteristic “play-of-color,” the iridescent effect visible in Opal when light strikes it. The color and intensity of this effect depend on the size and arrangement of these spheres.\nDeposits\nAndamooka is a small mining town in South Australia, located about 600 kilometers north of Adelaide. It lies near the salt lake known as Lake Torrens, in a landscape characterized by an arid climate and harsh conditions. Nevertheless, in the 1930s, rich Opal veins were discovered here, making Andamooka one of the oldest Opal mining fields in Australia.\nHistory\nThough Andamooka is not as famous as Coober Pedy or Lightning Ridge, Opal mining here has a long-standing tradition. Many of the mines remain family-run operations, often employing manual labor or small-scale machinery. In the past, Andamooka—like other Australian Opal fields—drew adventurers seeking valuable Opal seams in these tough conditions, hoping to discover a profitable find.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of Opal, renowned especially for the Lightning Ridge deposit in New South Wales. It has a dark body color (black, gray, or dark blue), which enhances the play of color. Black Opals often exhibit the most intense color spectrum—including red, green, blue, and purple.\nBoulder Opal Primarily mined in Queensland (northeastern Australia). It forms when Opal fills thin veins in iron-rich sandstone or other types of host rock (“boulder”). This variety usually retains part of the original rock, creating a contrasting base. Boulder Opals can have a darker tone, and therefore—similar to black Opals—feature a vivid play of color.\nCrystal Opal Characterized by a translucent or transparent background. In its raw state, it can sometimes appear nearly colorless, yet the iridescent flashes become apparent through a crystal-clear or milky base. Crystal Opals are found across Australia, with larger quantities coming from Coober Pedy.\nWhite (Light) Opal This type has a white or milky-white base color. It can exhibit colors as bright as those of black Opals, though the light background often “mutes” the contrast, resulting in a less intense effect. White Opal is especially common in Coober Pedy (South Australia) and is generally more affordable than black or boulder Opals.\nMatrix Opal A special variety in which Opal is embedded within a porous host rock (e.g., sandstone or ironstone). After treatment (impregnation), the colors can become much more vibrant, as the darker substrate intensifies the Opal’s play-of-color. Andamooka is chiefly known for these matrix Opals—referred to as Andamooka Matrix—which, once treated, can resemble rare black Opals from other localities.\nValue Opals from Andamooka are popular mainly for their relatively accessible prices and richly colored patterns. Nevertheless, high-quality pieces can still command substantial sums, especially those displaying intense color play or striking patterns (like a harlequin pattern).\nAustralian Opal – cabochon – Andamooka, Australia\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028174737733,"sku":"AO059","price":60.12,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/44966_photoroom-010-20250512-194716.jpg?v=1779381488"},{"product_id":"boulder-opal-114ct-cabochon-queensland-australia-bo010","title":"Boulder Opal 11.4ct – Cabochon – Queensland, Australia - BO010","description":"\u003cul\u003e\n\u003cli\u003eLocation: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 2.2g = 11.4ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 1.8 x 1.3 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of opals Australia offers—from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder opals from Australia’s Queensland, the fundamental formation process is the same, but the opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder opals can have a darker body tone, and thus can—like black opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder opals.\nMatrix Opal A distinct variety in which opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the opal’s play of color. Andamooka is especially famous for this type of matrix opal, known as Andamooka Matrix, which can resemble rare black opals from other localities once treated.\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028174803269,"sku":"BO010","price":96.31,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/6453_boulder-opal-11-4ct---cabochon---queensland--australia.jpg?v=1779381490"},{"product_id":"boulder-opal-3375ct-cabochon-koroit-queensland-australia-bo020","title":"Boulder Opal 33.75ct – Cabochon – Koroit, Queensland, Australia - BO020","description":"\u003cul\u003e\n\u003cli\u003eLocation: Koroit, Queensland, Australia\u003c\/li\u003e\n\u003cli\u003eWeight: 6.7g = 33.75ct\u003c\/li\u003e\n\u003cli\u003eDimensions: 3.2 x 2.5 x 0.5 cm\u003c\/li\u003e\n\u003cli\u003eDETAILED DESCRIPTION\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality opals. The quality of Australian opals is primarily due to their strong and pure play of color. Thanks to specific formation conditions, they often exhibit vivid, contrasting hues. This diversity is reflected in the many types of opals Australia offers—from black and boulder opals to crystal, white, and matrix opals. Australian opals are notably more durable and stable compared to many opals from other localities. Their naturally lower water content increases their ability to withstand temperature fluctuations and changes in humidity, which means they do not crack or dry out as easily, making them ideal for everyday wear in jewelry.\nFormation\nAustralian opals typically form in sedimentary rocks such as sandstones and clays, which are found in extensive basins (e.g., the Great Artesian Basin—a vast underground water system covering much of Australia’s interior). Water rich in silica gradually seeps into fine cracks or pores within the rock. Once this water evaporates or drains away, thin layers of silica remain in the cavities, which can eventually transform into opal.\nA key role is played by microscopic spheres of silicon dioxide (silica) that arrange themselves into a regular three-dimensional “crystal-like” structure. This arrangement produces the typical “play-of-color” phenomenon, the rainbow-like shimmer visible in opal when light strikes it. The color and intensity of this play-of-color depend on the size and arrangement of these spheres.\nIn the case of boulder opals from Australia’s Queensland, the fundamental formation process is the same, but the opal settles in thin veins or cavities within iron-rich parent rock. The dark color and high iron content of the host rock often enhance the contrast and richness of the opal’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder opals. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant opal-mining sites. The most famous places include Winton, Quilpie, Opalton, and Koroit, each of which significantly contributes to the global prestige of Australian opals.\nHistory\nOpal mining in Queensland began around the turn of the 19th and 20th centuries, when adventurers and settlers sought new means of livelihood in the unforgiving landscape. Conditions here remain harsh—heat and drought affect mining work but also help preserve opal deposits by minimizing damage from surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Australian Opals\nBlack Opal The rarest and most valuable type of opal, made famous by the Lightning Ridge deposit (New South Wales). It has a dark base color (black, gray, or dark blue), which emphasizes the play of color. Black opals often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opal ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when opal fills thin seams in ironstone or other types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder opals can have a darker body tone, and thus can—like black opals—exhibit a vibrant play of color.\nCrystal Opal Characterized by a translucent or transparent base. Sometimes it can be almost colorless in its uncut state, but the flashes of color shine through the crystal-clear or milky translucent base. Crystal opals occur throughout Australia, though many come from Coober Pedy.\nWhite (Light) Opal This variety has a white to milky-white base color. It can display similarly vibrant colors to black opal, but they tend to be less pronounced because the light background visually “mutes” the contrast. White opal is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder opals.\nMatrix Opal A distinct variety in which opal is dispersed within a porous host rock (such as sandstone or ironstone). After treatment (impregnation), the colors can become much more intense, as the darker background enhances the opal’s play of color. Andamooka is especially famous for this type of matrix opal, known as Andamooka Matrix, which can resemble rare black opals from other localities once treated.\nBoulder Opal – cabochon – Koroit, Queensland, Australia\u003c\/p\u003e","brand":"PeltramMinerals","offers":[{"title":"Default Title","offer_id":58028174901573,"sku":"BO020","price":239.15,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0881\/1659\/2965\/files\/43028_boulder-opal-33-75ct---cabochon---koroit--queensland--australia.jpg?v=1779381492"}],"url":"https:\/\/moldavite.it\/en\/collections\/opale-australiano.oembed?page=2","provider":"Moldavite.it","version":"1.0","type":"link"}