mineral

Amethyst (Quartz variety)

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Purple to violet (zoning visible in this sample), Luster: Vitreous, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Identified April 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to violet (zoning visible in this sample), Luster: Vitreous, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and geodes via precipitation from silica-rich fluids. The purple color comes from irradiation of iron impurities over millions of years.

Uses & applications

Primarily used as a gemstone in jewelry, decorative ornaments, and by mineral collectors for its aesthetic appeal.

Geological facts

Amethyst is the birthstone for February. Ancient Greeks believed it could prevent intoxication; the name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its distinct purple color, hexagonal crystal shape (if unbroken), and ability to scratch glass. Found commonly in Brazil, Uruguay, and Africa.