Smoky Quartz

Mohs 7Silicates
GroupSilicates
Mohs Hardness7
ColorsBrown, Gray, Black

About Smoky Quartz

A brown to gray quartz whose color comes from natural radiation acting on traces of aluminum in the crystal. In Scotland it is called cairngorm, after the mountains where it was once collected, and it is set in traditional Highland dress jewelry. Very dark, nearly black specimens are called morion. Heating can lighten or remove the color. It forms large clear crystals in the Swiss Alps and Brazil.

Related Gemstones