mineral

Amethyst

Crystalline Quartz (SiO2) with iron impurities

Hardness: 7 on the Mohs scale; Color: Pale lilac to deep purple; Luster: Vitreous (glass-like); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Pale lilac to deep purple
Luster: Vitreous (glass-like)

Identified February 20, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Pale lilac to deep purple; Luster: Vitreous (glass-like); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or hollow cavities called geodes, often within volcanic igneous rock. The purple color comes from irradiation of trivalent iron impurities within the quartz crystal lattice.

Uses & applications

Extensively used in jewelry (faceting and cabochons), metaphysical practices, and as decorative mineral specimens for collectors.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil in the 1700s. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identified by its purple hexagonal crystal points and its ability to scratch glass but not topaz. Commonly found in Brazil, Uruguay, Zambia, and Ontario. Collectors look for deep 'Siberian' purple hues and lack of visible inclusions.

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