mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

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

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

Identified March 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and hollow geodes, typically when silica-rich water precipitates in cavities of igneous volcanic rock after cooling. Its purple color comes from iron impurities and natural irradiation.

Uses & applications

Primary use in jewelry (faceting and cabochons), decorative carvings, and as popular specimens for mineral collectors and metaphysical practitioners.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness. It was once considered a 'Cardinal Gem' on par with diamonds until large deposits were found in Brazil.

Field identification & locations

Identify in the field by its distinct purple hue, glass-like luster, and lack of cleavage. Common locations include Brazil, Uruguay, Zambia, South Korea, and Ontario, Canada.