mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2 with impurities)

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

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

Identified June 1, 2026More mineral →

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Physical properties

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

Formation & geological history

Typically forms in hydrothermal veins or as linings within volcanic gas cavities (geodes) when silica-rich water crystallizes over millions of years. The color is due to irradiation and iron impurities.

Uses & applications

Primarily used in jewelry (faceting and cabochons), as decorative specimens for collectors, and in spiritual/metaphysical practices.

Geological facts

Amethyst is the birthstone for February. The name comes from the Ancient Greek word 'amethystos', which means 'not intoxicated', as they believed the stone could prevent drunkenness.

Field identification & locations

Identified by its purple color and hardness (it can scratch glass but cannot be scratched by a steel nail). Commonly found in Brazil, Uruguay, Zambia, and Canada. Look for crystal faces with facets at 60-degree angles.

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