mineral

Amethyst

Quartz (Silicon Dioxide, SiO2)

Hardness of 7 on the Mohs scale, purple to violet color, vitreous luster, hexagonal crystal system, conchoidal fracture, specific gravity of 2.65.

Identified July 30, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, purple to violet color, vitreous luster, hexagonal crystal system, conchoidal fracture, specific gravity of 2.65.

Formation & geological history

Formed within gas cavities (vesicles) in basaltic rocks, or as linings in hydrothermal veins, where silica-rich solutions deposit quartz crystals over millions of years.

Uses & applications

Widely used in jewelry, ornamental carvings, spiritual and metaphysical practices, and as collector specimens.

Geological facts

Amethyst was once as valuable as diamond, ruby, and emerald until large deposits were discovered in Brazil in the 19th century. Its purple color is due to irradiation and trace amounts of iron.

Field identification & locations

Easily identified by its distinct purple color and crystal point terminations. Commonly found in Brazil, Uruguay, Zambia, and the United States (such as Arizona).