mineral

Amethyst

Amethyst (SiO2 with Iron impurities)

Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous; Crystal structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Purple to violet
Luster: Vitreous

Identified March 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous; Crystal structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. It occurs when silica-rich water cools and crystallizes in rock cavities. Its purple color is caused by gamma irradiation of trivalent iron (Fe3+) impurities within the quartz lattice.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings) and as decorative specimens for collectors and interior design. Historically used for amulets.

Geological facts

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

Field identification & locations

Identify in the field by its characteristic purple hue 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 with red or blue flashes.