mineral

Amethyst

Quartz (Silicon Dioxide, SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, purple to violet color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified July 29, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, purple to violet color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in hydrothermal veins and gas cavities (vugs and geodes) in volcanic rocks, where silica-rich solutions cool and crystallize over millions of years.

Uses & applications

Widely used as a gemstone in jewelry, for ornamental carvings, and as a popular mineral specimen for collectors.

Geological facts

The purple color is caused by irradiation, iron impurities, and the presence of trace elements. Historically, amethyst was considered a precious gemstone of equal value to diamond and ruby until large deposits were discovered in Brazil.

Field identification & locations

Easily identified by its distinct purple coloration and hardness of 7, which scratches glass. Found worldwide, with major deposits in Brazil, Uruguay, Zambia, and the United States.