mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

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

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

Identified July 14, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and basaltic geodes through the precipitation of silica from aqueous solutions, colored by natural irradiation of trivalent iron (Fe3+). Often found in Cenozoic basalt cavities.

Uses & applications

Widely used in jewelry (faceting, cabochons), ornamental carvings, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

The color of Amethyst can fade if exposed to prolonged sunlight. It was once considered a 'Cardinal Gem' and was as valuable as diamonds until large deposits were found in Brazil in the 19th century.

Field identification & locations

Identified by its purple hue and hexagonal crystal habits. Often found in Brazil, Uruguay, Zambia, and South Korea. Look for its transparency and typical crystal points in volcanic rock cavities.