mineral

Amethyst

Silicon Dioxide (SiO2) containing Iron impurities

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

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

Identified April 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in silica-rich liquids inside volcanic geodes and cavities. The purple color is caused by trace amounts of iron irradiation in the quartz lattice. Predominant deposits are from the Mesozoic or Cenozoic periods.

Uses & applications

Primarily used as a gemstone in jewelry, decorative carvings, and as a popular collector's mineral specimen. Historically used as a talisman against intoxication.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated'. Until the discovery of large deposits in Brazil in the 19th century, it was considered a Precious Stone equal in value to Ruby and Emerald.

Field identification & locations

Identified by its distinctive purple hue and hexagonal crystal form in geodes. Commonly found in Brazil, Uruguay, and Zambia. Collectors look for deep saturation and high clarity.

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