{"product_id":"boulder-opal-22ct-cabochon-queensland-australia-bo004","title":"Opale boulder 22ct – Cabochon – Queensland, Australia - BO004","description":"\u003cul\u003e\n\u003cli\u003eLocalità: Queensland, Australia\u003c\/li\u003e\n\u003cli\u003ePeso: 4,4g = 22ct\u003c\/li\u003e\n\u003cli\u003eDimensioni: 3,3 x 1,2 x 0,6 cm\u003c\/li\u003e\n\u003cli\u003eDESCRIZIONE DETTAGLIATA\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eAustralia is renowned worldwide as the most important source of high-quality Opalees. The quality of Opale Australianoees 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 Opalees Australia offers—da black and boulder Opalees to crystal, white, and matrix Opalees. Opale Australianoees are notably more durable and stable compared to many Opalees da Altro 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\nOpale Australianoees 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 Opalee.\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 Opalee 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 Opalees da Australia’s Queensland, the fundamental formation process is the same, but the Opalee 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 Opalee’s color effects.\nLocalities\nQueensland is one of the key areas in Australia for boulder Opalees. It spans the continent’s northeast, where much of the interior is arid or semi-arid land. This region hosts significant Opalee-mining sites. The most famous places include Winton, Quilpie, Opaleeton, and Koroit, each of which significantly contributes to the global prestige of Opale Australianoees.\nHistory\nOpalee 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 Opalee deposits by minimizing damage da surface water. Many mines are still owned by small family businesses that rely on traditional techniques, supplemented by modern machinery.\nTypes of Opale Australianoees\nBlack OpaleeThe rarest and most valuable type of Opalee, 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 Opalees often display the most intense range of colors—red, green, blue, or purple.\nBoulder Opalee ✓\nPrimarily mined in Queensland (northeastern Australia). It forms when Opalee fills thin seams in ironstone or Altro types of parent rock (“boulder”). This type usually retains part of the original rock, creating a contrasting background. Boulder Opalees can have a darker body tone, and thus can—like black Opalees—exhibit a vibrant play of color.\nCrystal Opalee 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 Opalees occur throughout Australia, though many come da Coober Pedy.\nWhite (Light) Opalee This variety has a white to milky-white base color. It can display similarly vibrant colors to black Opalee, but they tend to be less pronounced because the light background visually “mutes” the contrast. White Opalee is most commonly found in Coober Pedy (South Australia) and is more affordable than black or boulder Opalees.\nMatrix OpaleeA distinct variety in which Opalee 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 Opalee’s play of color. Andamooka is especially famous for this type of matrix Opalee, known as Andamooka Matrix, which can resemble rare black Opalees da Altro 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","url":"https:\/\/moldavite.it\/products\/boulder-opal-22ct-cabochon-queensland-australia-bo004","provider":"Moldavite.it","version":"1.0","type":"link"}