mineral

Amethyst (Faceted)

Amethyst (Silicon Dioxide with iron impurities, SiO2)

Hardness: 7 (Mohs scale), Color: Deep purple to violet, Luster: Vitreous (glassy), Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Identified April 27, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Deep purple to violet, Luster: Vitreous (glassy), Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes within volcanic rock. The purple color is caused by gamma irradiation of iron impurities in the quartz structure. Found in various geological ages ranging from Cretaceous to recent deposits.

Uses & applications

Primary use is in jewelry (rings, pendants, earrings), decorative lapidary arts, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Amethyst was considered a 'Cardinal Gem' until the 18th century, ranking alongside diamonds and rubies in value until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple color and hexagonal prism habits in the wild. While common in Brazil and Uruguay, high-quality deep purple stones are rarer. Look for 'tiger stripe' inclusions under magnification to verify natural origin.

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