mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous/glassy; Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous/glassy

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous/glassy; Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes when silica-rich water cools. The purple color comes from irradiation of iron impurities within the quartz crystal lattice. Found in volcanic rocks and metamorphic deposits.

Uses & applications

Extensively used in jewelry (rings, necklaces, earrings), as decorative specimens for collectors, and in metaphysical practices as a healing stone.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' along with diamond, ruby, emerald, and sapphire until large deposits were found in Brazil. The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its distinct purple hue and quartz-like crystal habit. To find in the field, look for volcanic basalt areas or geode-bearing layers. Common in Brazil, Uruguay, Zambia, and Ontario, Canada.