mineral

Amethyst

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

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

Identified June 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; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich water cools. The purple color comes from iron impurities and natural irradiation.

Uses & applications

Extensively used in jewelry (faceting and cabochons), ornamental carvings, and as a popular collector specimen.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its distinctive purple hue and hardness (scratching glass). Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for even color distribution.