mineral

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

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

Identified May 14, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in silica-rich hydrothermal veins or within gas cavities (geodes) in igneous rocks. The purple color is caused by gamma irradiation of trace iron impurities within the quartz crystal lattice.

Uses & applications

Primary use is in jewelry as a gemstone, lapidary arts, and as a popular collector's mineral specimen.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify by its distinct purple hue and quartz-like hexagonal crystal habit. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep, uniform color and high clarity.

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