mineral

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

Hardness: 7 (Mohs scale); Color: Purple to violet due to irradiation and iron impurities; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified July 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or inside volcanic geodes (amygdules) when silica-rich water deposits crystals. The purple color is caused by the presence of trace amounts of trivalent iron (Fe3+) and natural gamma radiation within the host rock.

Uses & applications

Extensively used in jewelry (rings, necklaces), as decorative geodes, and in metaphysical/collecting communities. High-grade specimens are faceted into gemstones.

Geological facts

Amethyst is the birthstone for February. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify by its distinct purple hue and 7 hardness (it will scratch glass). Often shows color zoning or white quartz bands (chevron amethyst). Commonly found in Brazil, Uruguay, and Zambia.

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