Larsenite is a mineral that belongs to the arsenate mineral group. It is a rare mineral that was first discovered in 1961 in the Ivigtut Cryolite deposit in Greenland. The mineral was named after the Danish mineralogists brothers, Alfred and Edgar Larsen.
Larsenite has a unique crystal structure and is known for its vibrant and attractive color. It generally occurs as small, prismatic crystals, but can also be found in fibrous or radial aggregates. The color of larsenite can vary, but it is most commonly a rich green or bluish-green, sometimes with hints of yellow or brown.
Chemically, larsenite is an arsenate mineral that contains calcium, manganese, and fluorine. Its chemical formula is CaNaAlMn2(AsO4)3F, which reflects the presence of these elements. It is mainly formed in hydrothermal veins, which are created when hot fluids rich in minerals circulate through cracks in the Earth's crust.
Larsenite is known for its strong pleochroism, meaning it can exhibit different colors when viewed from different angles. It also has a high refractive index and typically displays a vitreous to silky luster. Its hardness on the Mohs scale is around 5 to 5.5, making it relatively soft compared to other minerals.
Due to its rarity and aesthetic appeal, larsenite is sought after by collectors and enthusiasts of rare minerals. It is also studied by scientists and researchers to gain insights into mineral formations and geology.
