mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: light to deep purple/lavender, Luster: Vitreous, Crystal structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture)

Identified July 14, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: light to deep purple/lavender, Luster: Vitreous, Crystal structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture)

Formation & geological history

Forms in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color is caused by natural irradiation of trace iron impurities replacing silicon in the crystal lattice.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative carvings, and as a popular specimen for mineral collectors and crystal healing enthusiasts.

Geological facts

The name comes from the ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. Ancient Egyptians used it for intaglio engraved gems.

Field identification & locations

Identify by its distinct purple hue, glass-like luster, and lack of cleavage. It is famously found in massive quantities in Brazil and Uruguay, but also occurs in Arizona and Zambia.