mineral

Amethyst

Silicon dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet, Lavender; Luster: Vitreous/Glassy; Crystal structure: Trigonal; Cleavage: None; Fracture: Conchoidal; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, Lavender
Luster: Vitreous/Glassy

Identified June 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, Lavender; Luster: Vitreous/Glassy; Crystal structure: Trigonal; Cleavage: None; Fracture: Conchoidal; Specific gravity: 2.65

Formation & geological history

Forms in geodes or cavities within igneous rocks through hydrothermal processes. The purple color comes from irradiation, iron impurities, and the presence of trace elements. Age varies by location, often associated with Cretaceous or Tertiary volcanic activity.

Uses & applications

Primarily used in jewelry (rings, necklaces, earrings), ornamental carvings, and as a popular collector's specimen for chakra or metaphysical purposes.

Geological facts

Until the discovery of large deposits in Brazil in the 19th century, amethyst was considered one of the 'Cardinal Gems' and was as expensive as diamonds and rubies. It is the birthstone for February.

Field identification & locations

Identify by its distinct purple color and hexagonal crystal termination. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for transparent to translucent crystals in basaltic clusters.