mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Purple, violet; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple, violet
Luster: Vitreous

Identified June 4, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple, violet; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich water deposits crystals. The purple color comes from irradiation of trivalent iron (Fe3+) impurities within the quartz lattice.

Uses & applications

Primarily used in jewelry (as a semi-precious gemstone), ornamental carvings, and widely collected as mineral specimens for metaphysical or aesthetic purposes.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. Its name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify by its distinctive purple hue and hexagonal crystal prisms if uncut. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep 'Siberian' purple with red/blue flashes.