mineral

Amethyst (Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Pale to deep purple/violet, Luster: Vitreous (glassy), Crystal system: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified May 22, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Pale to deep purple/violet, Luster: Vitreous (glassy), Crystal system: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings in geodes. The purple color comes from irradiation of trivalent iron impurities (Fe3+) in the silica structure. Can be found in igneous rocks like basalt or rhyolite.

Uses & applications

Predominantly used as a gemstone for jewelry (rings, necklaces, earrings), meditation aid, and as decorative mineral specimens for collectors.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' along with diamond, ruby, sapphire, and emerald until large deposits were found in Brazil. The name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its hardness (scratches glass), purple hue, and lack of cleavage. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep saturation and clarity.