mineral

Amethyst Quartz Crystal

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale. Color: Violet to pale purple tip fading into clear/white quartz base. Luster: Vitreous (glassy). Crystal Structure: Hexagonal prism terminated by rhombohedra. Cleavage: None (conchoidal fracture).

Hardness: 7 on Mohs scale
Luster: Vitreous (glassy)

Identified July 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) where silica-rich fluids deposit quartz crystals at moderate temperatures. The purple hue is caused by natural irradiation of trace ferric iron (Fe3+) integrated into the crystal lattice.

Uses & applications

Widely used in jewelry, lapidary arts, mineral specimen collecting, and decorative crafts.

Geological facts

Amethyst gets its name from the Ancient Greek 'amethystos', meaning 'not intoxicated', as the ancients believed it prevented drunkenness. Highly prized historically alongside ruby, emerald, and sapphire until large deposits were found in South America.

Field identification & locations

Identified by its hexagonal prismatic crystal habit, hardness of 7 (will scratch glass), and signature purple color zoning at the termination. Common sources include Brazil, Uruguay, Madagascar, Zambia, and Veracruz, Mexico.

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