mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Purple to violet due to iron impurities and irradiation; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Purple to violet due to iron impurities and irradiation
Luster: Vitreous (glass-like)

Identified March 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as linings in geodes within igneous rocks (primarily basalt) when silica-rich water crystallizes over time. The purple color is caused by natural irradiation and the presence of trace iron (Fe3+).

Uses & applications

Predominantly used as a gemstone in jewelry (rings, necklaces, earrings), as decorative ornamental objects, and widely collected by mineral enthusiasts for metaphysical or aesthetic purposes.

Geological facts

Amethyst was once considered a 'Cardinal Gem' and was as valuable as diamond until large deposits were found in Brazil. The name comes from the Greek word 'amethystos,' meaning 'not intoxicated,' as ancient Greeks believed it prevented drunkenness.

Field identification & locations

Identify in the field by its distinct purple color, 6-sided prismatic crystals, and lack of cleavage (it breaks like glass). Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep 'Siberian' purple hues.