mineral

Amethyst

Silicon dioxide / Quartz (SiO2+Fe4+)

Hardness: 7.0 Mohs scale; Color: Purple to violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7
Color: Purple to violet
Luster: Vitreous/Glassy

Identified April 9, 2026More mineral →

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Physical properties

Hardness: 7.0 Mohs scale; Color: Purple to violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and geodes via precipitation from mineral-rich waters. The purple color comes from irradiation, iron impurities, and the presence of trace elements. Age varies globally from Precambrian to more recent geological eras.

Uses & applications

Predominantly used as a gemstone in jewelry, for ornamental carvings, and as a popular specimen for mineral collectors.

Geological facts

Amethyst was once considered as valuable as diamonds until large deposits were discovered in Brazil in the 19th century. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was once believed to prevent drunkenness.

Field identification & locations

Identify by its characteristic purple hue and vitreous luster. In the field, look for hexagonal prism crystals within geodes. Found commonly in Brazil, Uruguay, Zambia, and Ontario, Canada.