mineral

Amethyst

Silicon Dioxide (SiO2) with trace Iron (Fe) impurities

Hardness: 7.0 Mohs; Color: Pale lilac to deep purple; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7
Color: Pale lilac to deep purple
Luster: Vitreous

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7.0 Mohs; Color: Pale lilac to deep purple; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in geode cavities and hydrothermal veins where silica-rich fluids cool and crystallize. The purple color is caused by natural irradiation of trace iron impurities within the quartz crystal lattice. Found in volcanic rocks (basalts) and metamorphic environments.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings), as decorative household display pieces (geodes and cathedrals), and is highly valued by mineral collectors and the metaphysical community.

Geological facts

Until the 18th century, amethyst was considered one of the 'Cardinal Gems' alongside diamond, ruby, sapphire, and emerald. Ancient Greeks believed it could prevent intoxication; the name comes from 'amethystos,' meaning 'not drunken.'

Field identification & locations

Identify by its characteristic purple hue, 7.0 hardness (will scratch glass), and lack of cleavage. Key locations include Brazil, Uruguay, Zambia, and Ontario. Collectors should look for deep 'Siberian' purple saturation with red or blue flashes for highest value.

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