mineral

Amethyst

Amethyst (Purple Quartz); formula: SiO2 (Silicon Dioxide)

Hardness: 7 on Mohs scale; Color: Ranges from light lavender to deep violet; Luster: Vitreous (glass-like); Crystal structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Ranges from light lavender to deep violet
Luster: Vitreous (glass-like)

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed in geodes or hydrothermal veins by the precipitation of quartz from silica-rich fluids. The purple color is caused by irradiation of iron impurities within the crystal lattice. Most deposits are found in volcanic rocks (basalt flows) or metamorphic environments.

Uses & applications

Primarily used as a gemstone in jewelry, for ornamental carvings, and as a popular specimen for mineral collectors and 'spiritual healing' practitioners. It is the birthstone for February.

Geological facts

Until the 18th century, amethyst was considered one of the five cardinal gemstones alongside diamonds and rubies. The name comes from the Greek word 'amethystos', meaning 'not intoxicated', due to an ancient belief that it could prevent drunkenness.

Field identification & locations

Identify in the field by its distinct purple hue, hexagonal crystal points, and lack of cleavage (it breaks like glass). It is commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for 'color zoning' where the purple is concentrated at the tips.

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