Amethyst a well known mineral, purple variety of Quartz. Amethyst is most prevalent as pyramidal crystals, but localities like Mexican occurrences are well-known for producing tall prismatic crystals, highly regarded by collectors. Amethyst occurs in primary hues from a light lavender or pale violet, to a deep purple. Amethyst may exhibit one or both secondary hues, red and blue. Amethyst frequently shows color zoning, with the most intense color typically found at the crystal terminations.