Aragonite blue - sphere 431g Afghanistan

Aragonite (calcium carbonate) is formed under low-temperature and surface conditions, it is a late mineral of hydrothermal deposits and epithermal veins, it is abundant in thermal springs and geysers. It is formed during the decomposition of calcium basalts and their lavas by autohydration. It is present in sediments or is present as a component of stalactites. They form short or long prismatic crystals, columnar or fibrous crystals, they form stalked, pizolithic (pea) or hot-spring (hot-spring) aggregates. Twin fusion is known, rarely the fusion of three crystals is known, resulting in a pseudohexagonal appearance. The colors are white, gray, yellow-white, greenish, reddish, yellow-white, bluish, purple, also colorless. It is transparent to translucent, pleochroism is not known, it is thermoluminescent. White or colorless scratch. Glassy luster on crystal surfaces, pitch on fracture surfaces.