Amethyst is a violet variety of the mineral quartz. Other members of the quartz family include citrine and smoky quartz.
It has been used in jewelry since ancient Egyptian times, and until the 19th century it was extremely rare and expensive. Now that extensive deposits have been discovered in Brazil and Africa it has become much more affordable.
While the largest deposits of amethyst are in Brazil, there are also substantial quantities found in Africa. African sources for amethyst include Zambia, Nigeria, Tanzania and Burundi. Zambian amethyst is known for its very intense color, though it is frequently more flawed than the stones from other sources.
The new source in Burundi is producing some excellent quality stones similar to the finest Brazilian material.
Because amethyst is freely available and inexpensive, it can be cut into any shape imaginable. Amethyst is frequently available in very large sizes. Huge crystals and geodes are sometimes found, such as one in the Smithsonian which weighs a massive 400 pounds.
Amethyst has long been associated with the Christian church. Bishops wore the stone in rings and it was the stone said to be worn by St. Valentine. In the Middle Ages it was considered a stone of royalty and it is found in several pieces of the British crown jewels. It was also a popular gem with the ancient Greeks, being associated with the god of wine, Bacchus. Legend has it that the stone is a talisman against drunkenness. For this reason, it was frequently shaped into drinking vessels.
Amethyst color varies from pale lavender through to intense purple. The darker tones are considered the most valuable color, though the paler stones (called Rose de France amethyst) can also be very beautiful when well cut. Some of the very best amethyst has a hint of red or blue under different lights. Like other quartz varieties, it has good hardness and durability and is excellent value for money. Amethyst from some sources can be heat treated to orange citrine, or irradiated to green.
Amethyst is the traditional birthstone for February and one of the zodiac stones for Pisces.