mineral

Amethyst

Quartz (Silicon Dioxide) with Iron impurities, SiO2

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or cavities (geodes) within igneous rocks. The purple color is caused by irradiation of trivalent iron impurities (Fe3+) within the quartz structure. These can range in age from millions to hundreds of millions of years.

Uses & applications

Primarily used in jewelry as a semi-precious gemstone. Also highly popular for mineral collecting, lapidary arts, and ornamental decoration.

Geological facts

Amethyst was considered a Cardinal Gem (one of the five most precious) until the discovery of large deposits in Brazil in the 1700s. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify in the field by its distinct purple color, hexagonal crystal shape, and inability to be scratched by a steel knife. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep 'Siberian' purple hues with red or blue flashes.

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