• Type: Iron meteorite, IVA octahedrite
• Location: Norrbotten, Sweden
• Weight: 9.2g
• Dimensions: 3.7 x 1.9 x 0.1 cm
• Year of finding: 1906
• Known total weight: 230 kg
• Surface treatment: cut, Polished slice
• DETAILED DESCRIPTION

Muonionalusta Meteorite – One of the Oldest Known Meteorite Falls on Earth The Muonionalusta meteorite is estimated to have fallen to Earth around one million years BCE, making it one of the oldest known meteorite falls. It originated from the asteroid belt between Mars and Jupiter, and its age is estimated to be over 4.5 billion years. This belt contains many asteroids and meteorites that sometimes break off and travel through space until they eventually impact Earth. Muonionalusta is a fragment of one such asteroid that survived atmospheric entry and struck the Earth's surface. Discovery and Classification The first fragment of this meteorite was discovered in 1906, with others found throughout the 20th and 21st centuries, some weighing several hundred kilograms. It is classified as a fine IVA octahedrite and is particularly known for its remarkable Widmanstätten patterns, which are irregular crystal structures of iron-nickel. These patterns are formed by the slow cooling of the metal in space. Not all iron meteorites exhibit these patterns. To reveal them, the surface must be polished and etched with diluted nitric acid, preferably mixed with methanol. Composition Muonionalusta is composed of approximately 91% iron, 8.4% nickel, small amounts of rare elements such as gallium, germanium, and iridium, and various minerals.