Amethyst is a violet variety of quartz, and its name comes from the Koine Greek αμέθυστος amethystos from α- a-, "not" and μεθύσκω methysko / μεθώ metho, "intoxicate", a reference to the belief that the stone protected its owner from drunkenness. Ancient Greeks wore amethyst and carved drinking vessels from it in the belief that it would prevent intoxication. Amethyst is a semiprecious stone and is often used in jewelry.

Amethyst is a three-dimensional network of tetrahedra where the silicon atoms are in the center and are surrounded by four oxygen atoms located at the vertices of a tetrahedron. This structure is quite rigid and results in quartzs hardness and resistance to weathering. The hardness of the mineral is the same as quartz, thus making it suitable for use in jewelry.

Amethyst is found in many locations around the world, and its purple color can range from a light lilac to a deep, intense royal purple, and from brownish to vivid. Amethyst also commonly shows what is called color zoning, which in the case of amethyst usually consists of angular zones of darker to lighter color.

Amethyst is believed to have spiritual and healing properties. It is often viewed as a stone of peace, and some believe amethysts calming presence produces soothing dreams by bringing the dreamer more in tune with the Divine. This clarity and peacefulness also extends to the waking mind, and amethysts are said to help the mind flow freely in both mental and metaphysical dimensions. Many psychics keep this gem with their tarot cards or other oracular instruments.