A purple variety of quartz that is a semi-precious gemstone and a member of the hexagonal crystal structure is called amethyst. Amethyst occurs in various violet and purple tones and has a glassy shine. Amethyst is a stunning gemstone that has been prized and used for a variety of purposes for numerous years. Calmness, discernment, and spiritual healing are associated with amethyst. Amethyst is a symbol of purity and a link to the spiritual world.