Amethyst is a variety of quartz that forms fine pyramidal crystals. Its name is of Greek origin. Its hardness is 7 and its specific gravity 2.65. It crystallizes in the orthorhombic crystallographic system and forms crystals in the shape of hexagonal prisms. It is an impressively beautiful material and meets all specifications to be used for crafting jewelry. However, its price is not very high because it is mined in large quantities. Ancient Greeks believed that amethyst could guard against drunkenness. In the Bible it is identified with the ninth tribe of Issachar and adorns the vestments of the high priest of the temple of Solomon. In the Apocalypse of John, it is the twelfth stone of the new Jerusalem. It is found in sedimentary rocks of Brazil, Uruguay, Mexico, USA, the Urals, the Czech Republic and Switzerland.