mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

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

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

Identified March 25, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or as linings inside volcanic geodes. The purple color is a result of irradiation of trivalent iron (Fe3+) impurities in the quartz structure. Most specimens range from a few thousand to several million years old depending on the host rock formation.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings), as decorative pieces for home decor, and highly valued by mineral collectors and metaphysical practitioners.

Geological facts

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

Field identification & locations

Identify in the field by its distinctive purple color and lack of cleavage (it breaks like glass). Commonly found in Brazil, Uruguay, Zambia, and Ontario, Canada. Collectors should look for deep, uniform color and transparency.

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