mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

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

Identified July 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and basaltic geodes through the deposition of silica-rich water. Its purple color comes from irradiation of iron impurities in the quartz structure. Typical age varies from millions to hundreds of millions of years.

Uses & applications

Extensively used in jewelry (rings, necklaces), as decorative geodes, for collection, and in alternative healing practices.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. Its name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its distinctive purple color and quartz-like vitreous luster. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep saturation of color and clarity.