mineral

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

AI-generated identification · may be incorrect

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

Hardness: 7 (Mohs scale)
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified July 16, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and basaltic geodes. The purple color is caused by irradiation, iron impurities, and the presence of trace elements. Found in rocks of various ages ranging from Precambrian to recent vulcanism.

Uses & applications

Used extensively in jewelry (faceted or cabochon), ornamental carvings, and as a popular mineral specimen for collectors.

Geological facts

Amethyst is the birthstone for February. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habits. Often found in geode cavities in volcanic rock. Common locations include Brazil, Uruguay, Zambia, and Ontario.