mineral

Amethyst Quartz Crust

Crystalline Silicon Dioxide with Iron impurities (SiO2)

Hardness: 7 on Mohs scale; Color: Purple to violet on one side, colorless to white on the other; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Luster: Vitreous (glassy)

Identified June 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or cavities (geodes) where silica-rich fluids cooled and crystallized. The purple hue results from iron impurities and natural irradiation. Found in volcanic basalt vugs or metamorphic rocks.

Uses & applications

Popular for use in jewelry (faceted or cabochon), decorative home decor, metaphysical collecting, and spiritual practices.

Geological facts

Amethyst was considered a precious stone on par with diamonds until large deposits were discovered in Brazil in the 1700s. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by the distinct hexagonal prism crystal habits and purple coloration. Look for 'zoning' where color is unevenly distributed. Commonly found in Brazil, Uruguay, and Thunder Bay, Canada.

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Mineral/Rock

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Metamorphic Rock

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mineral