1/2 Lbs. Amethyst Crystals, Brazil Chemical Composition: Silicon Dioxide Hardness: 7 Ideal for Orgonite Projects. 30 to 40 crystals per 1/2 Lbs. Amethyst has been known as the most highly prized form of quartz. It is the presence of manganese in quartz that produces the purple color, and iron content varies the coloration. Amethyst may be found throughout the world; our specimens are from ...