mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with iron impurities)

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

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

Identified March 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in igneous or metamorphic environments, often within volcanic geodes. The purple color results from irradiation, iron impurities, and the presence of trace elements. While found in formations of many ages, major deposits range from Cretaceous to modern.

Uses & applications

Primarily used as a gemstone in jewelry, for decorative items, and by collectors for its aesthetic and spiritual perceived value.

Geological facts

Historically considered a 'Cardinal Gem' until the discovery of large deposits in Brazil in the 19th century. The 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 hue and hexagonal crystal habit when in geodes. Often found in basaltic rocks. Common locations include Brazil, Uruguay, Zambia, and Ontario, Canada.

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