mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

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 July 10, 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 cavities (geodes) of igneous rocks through hydrothermal processes when silica-rich water containing trace amounts of iron is subjected to natural irradiation. Found in volcanic basalt vugs.

Uses & applications

Primarily used in jewelry, as birthstones, for decorative carvings, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Amethyst was once considered a 'Cardial Gem' on par with diamond and ruby until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its distinctive purple color and hexagonal crystal habit (though this is a tumbled specimen). Can be found in Brazil, Uruguay, Zambia, and South Korea. Practitioners identify it by its clarity and saturation of purple.

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Mineral

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Mineral/Rock