mineral

Amethyst

Quartz (Silicon Dioxide with iron impurities) - SiO2

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

Hardness: 7 Mohs
Color: Purple, violet
Luster: Vitreous

Identified June 11, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Purple, violet; 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). The purple color results from irradiation, iron impurities, and the presence of trace elements during the cooling of silica-rich solutions in volcanic rock cavities.

Uses & applications

Extensively used in jewelry (rings, necklaces), as decorative omaments, and highly sought after by mineral collectors for its aesthetic appeal.

Geological facts

Amethyst was considered a precious stone on par with diamond until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habit (if not tumbled). Tumbled specimens like this show conchoidal fractures. Commonly found in Brazil, Uruguay, and Madagascar.

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