mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

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

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

Identified July 19, 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 (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Forms in hydrothermal veins and cavities (geodes) within igneous rocks. The purple color is caused by irradiation of trivalent iron impurities (Fe3+) in the quartz structure. Most specimens are from the Cenozoic era.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings), as decorative ornamental pieces, and is highly popular among mineral collectors and the metaphysical community.

Geological facts

Until the discovery of large deposits in Brazil in the 19th century, amethyst was as expensive as ruby and emerald. It is the birthstone for February and was once believed by ancient Greeks to prevent intoxication.

Field identification & locations

Identify by its distinctive purple color and quartz-like hardness (scratches glass). Common locations include Brazil, Uruguay, Zambia, and Ontario, Canada. Look for hexagonal crystal points in volcanic geodes during field identification.