mineral

Amethyst (Purple Quartz)

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Pale lilac to deep reddish-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 reddish-purple
Luster: Vitreous (glassy)

Identified April 5, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale lilac to deep reddish-purple; 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 within volcanic rock gas cavities (geodes). The purple color is caused by natural irradiation or iron impurities. Found mostly in Cenozoic era basaltic rocks.

Uses & applications

Primarily used in jewelry (faceting and cabochons), holistic healing practices, and as decorative collector specimens/ornaments.

Geological facts

Amethyst is the birthstone for February. Its name comes from the Koine Greek 'amethystos', meaning 'not intoxicated', due to an ancient belief that the stone protected its owner from drunkenness.

Field identification & locations

Identify by its characteristic purple zoning, hardness of 7 (scratches glass but not vice-versa), and lack of cleavage. Commonly found in Brazil, Uruguay, and Zambia.