mineral

Amethyst

Silicon dioxide with iron impurities (SiO2 + Fe3+)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous/glassy, Crystal structure: Trigonal (Hexagonal prisms), Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous/glassy, Crystal structure: Trigonal (Hexagonal prisms), Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings inside volcanic geodes. The purple color comes from natural irradiation of trace amounts of iron within the quartz crystal lattice.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings) and as decorative specimens for mineral collectors.

Geological facts

Amethyst was considered a 'Precious Stone' alongside Diamond, Sapphire, Ruby, and Emerald until large deposits were found in Brazil in the 19th century. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its distinct purple hue, hexagonal crystal shape (if present), and ability to scratch glass. Commonly found in Brazil, Uruguay, and Africa.