Rock Identifier
Amethyst (Quartz (SiO2)) — mineral
mineral

Amethyst

Quartz (SiO2)

AI-generated identification · may be incorrect

Mohs hardness of 7, purple to violet color, vitreous luster, trigonal crystal system, conchoidal fracture, no true cleavage, specific gravity of 2.65

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Physical properties

Mohs hardness of 7, purple to violet color, vitreous luster, trigonal crystal system, conchoidal fracture, no true cleavage, specific gravity of 2.65

Formation & geological history

Forms within gas cavities in volcanic rocks (vesicles in basalt) through hydrothermal solutions containing dissolved silica and iron impurities subjected to natural irradiation over millions of years

Uses & applications

Widely used as a gemstone in jewelry, ornamental carvings, and appreciated as a mineral specimen for crystal healing and collecting

Geological facts

The purple color is caused by irradiation and iron impurities substituting for silicon in the crystal lattice; historical cultures valued it as a talisman to prevent drunkenness

Field identification & locations

Easily identified by its distinct purple coloration and hardness of 7; commonly found in Brazil, Uruguay, Zambia, and the United States

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