Quantity: 1 kilogram Average size range: 4 to 7 millimeters Amethyst is a violet gemstone that occurs when quartz containing significant iron impurities and other trace elements undergoes natural geological irradiation over long periods of time, altering the color. Variations in color occur based on the amount of iron and the specific trace elements present in the original quartz. Amethyst Tumbled, Crystal River, Tumbling, Confetti, The Original, Violet, Amethyst, Chips, Gems