mineral

Amethyst

Silicon Dioxide (SiO2) with trace Iron (Fe)

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal (Hexagonal habit); Cleavage: None; Specific gravity: 2.65

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

Identified March 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal (Hexagonal habit); Cleavage: None; Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and basaltic cavities (geodes) when silica-rich water precipitates quartz over millions of years. The purple color is caused by natural irradiation of trace iron impurities.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative crystal specimens, and in metaphysical practices.

Geological facts

Amethyst was considered a Cardinal Gem until the 18th century, ranking alongside diamonds and rubies in value until large deposits were found in Brazil. The name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its purple hue, hexagonal prismatic crystal shape, and conchoidal fracture. Commonly found in Brazil, Uruguay, Zambia, and Ontario. Collectors look for deep saturation and clarity.

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