mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs), Color: Purple to violet with white/clear quartz banding, Luster: Vitreous (glassy) when polished, Crystal structure: Trigonal/Hexagonal, Specific Gravity: 2.65

Identified June 12, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs), Color: Purple to violet with white/clear quartz banding, Luster: Vitreous (glassy) when polished, Crystal structure: Trigonal/Hexagonal, Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or volcanic geodes where silica-rich fluids permeate cavities. The purple color is caused by irradiation of trivalent iron (Fe3+) in the quartz structure.

Uses & applications

Extensively used in jewelry, lapidary arts (carvings and polished shapes), and as a popular collector's mineral.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' along with diamond and ruby. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Commonly found in Brazil, Uruguay, and Zambia. Identify by its purple color, hardness (it can scratch glass), and lack of cleavage. Often shows 'color zoning' or translucent banding.