Amethyst is a variety of Quartz. It contains iron and other trace minerals within its structure. Its hardness is a 7 on the Mohs scale. The ancient Greeks wore amethyst and carved drinking vessels from it in the belief that it would prevent intoxication.
Amethyst is especially supportive of the emotional body, bringing those who are overworked, overstressed, or overwhelmed back to center. It eases the mental anxieties that lead to physical tension and headaches and is a great crystal to calm those who tend to be hot-headed and easily angered.