mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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 June 28, 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 within hydrothermal veins or volcanic geodes when silica-rich fluids cool and crystallize over millions of years. The purple color is caused by gamma irradiation of trivalent iron impurities within the quartz structure.

Uses & applications

Primarily used in jewelry, as decorative display pieces, and in metaphysical or spiritual practices. Historically used for amulets and drinking vessels.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as ancient Greeks believed the stone could prevent drunkenness. It was considered a Cardinal Gem until the discovery of large deposits in Brazil in the 1700s.

Field identification & locations

Identify by its characteristic purple color and ability to scratch glass. It often shows color zoning. Commonly found in Brazil, Uruguay, Zambia, and various locations in North America.

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