gemstone

Amethyst

Crystalline Quartz (SiO2 with iron impurities)

AI-generated identification · may be incorrect

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

Hardness: 7 on Mohs scale
Color: Purple to deep violet
Luster: Vitreous/glassy

Identified July 13, 2026More gemstone →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or as linings within volcanic rock cavities (geodes). The purple color is caused by natural irradiation of trace iron impurities within the quartz lattice. Found in regions with ancient basaltic or volcanic history.

Uses & applications

Used extensively in jewelry (rings, necklaces, carvings), as decorative specimens for collectors, and in alternative healing practices (metaphysical uses).

Geological facts

Amethyst was considered a 'Cardinal Gem' and was as valuable as diamond until large deposits were found in Brazil. Its name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify in the field by its distinct purple color and 6-sided crystal habit. Found globally with major commercial deposits in Brazil, Uruguay, Zambia, and Canada. Collectors should look for deep uniform color and high transparency.