Amethyst is a purple variety of quartz. It can range in color from a light violet to a deep purple. It is found as crystals in igneous rocks. It is available commercially in many forms. Large geodes called cathedrals are sometimes bigger than a man. Broken pieces of these geodes are called druz. It is sometimes cut into slabs and also sold as single points. Amethyst is used in jewelry and other decorative pieces. Most of the worldÂ’s supply of amethyst comes from Brazil. Uruguay produces a much smaller amount but many consider amethyst from Uruguay to be the highest quality because of its clarity and its rich dark purple color. Hardness: hard (7)