mineral

Amethyst (Quartz)

Amethyst (SiO2 with iron impurities)

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

Hardness: 7 (Mohs scale)
Color: pale lilac to deep purple
Luster: Vitreous/glassy

Identified June 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and volcanic geodes when silica-rich water cools. The purple color is caused by irradiation and trivalent iron impurities within the crystal lattice.

Uses & applications

Primarily used in jewelry (faceting and cabochons), decorative ornaments, and as a popular collectible for mineral enthusiasts and spiritual practices.

Geological facts

Amethyst was considered a precious stone on par with Diamond until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its characteristic purple hue and hexagonal crystal faces. Look for 'macrozonal' color patterns. Common in Brazil, Uruguay, Zambia, and South Korea.

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