mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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 June 26, 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 or as linings in geodes. The purple color results from irradiation of trivalent iron impurities within the quartz crystal lattice. Specimens range from thousands to millions of years old.

Uses & applications

Primarily used in jewelry (faceting, cabochons), ornamental decoration, and as a popular specimen for mineral collectors. Historically used to ward off intoxication.

Geological facts

Amethyst was considered a 'Cardinal Gem' until large deposits were found in Brazil, making it more accessible. Its name comes from the Greek word 'amethystos,' meaning 'not intoxicated.'

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habit if untumbled. Found commonly in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for depth of color and clarity.

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