mineral

Amethyst

Crystalline Silicon Dioxide with Iron impurities (SiO2)

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

Hardness: 7 on Mohs scale
Color: Purple, violet, to pale lavender
Luster: Vitreous

Identified March 15, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and hollow rocks (geodes) when silica-rich water cools. The purple color comes from irradiation of trivalent iron (Fe3+) in the quartz structure. Found in volcanic rocks of all ages.

Uses & applications

Widely used in jewelry (rings, necklaces, earrings), as decorative specimens for collectors, and in alternative healing practices. In the past, it was considered a precious stone equal to Ruby and Emerald.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. Heat treatment can turn amethyst yellow or orange, resulting in Citrine.

Field identification & locations

Identified by its purple color and hexagonal prism shape. Commonly found in Brazil, Uruguay, and Zambia. Collectors look for deep saturation and clarity without visible zoning.

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