mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 Mohs; Color: Purple to deep violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None; Specific Gravity: 2.65

Hardness: 7 Mohs
Color: Purple to deep violet
Luster: Vitreous (glassy)

Identified July 12, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Purple to deep violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and geodes, often as a result of volcanic activity where Mineral-rich water fills cavities. The purple color is caused by irradiation and iron impurities in the quartz lattice.

Uses & applications

Extensively used in jewelry (faceting and cabochons), carvings, decorative home decor, and crystal healing practices.

Geological facts

Amethyst was once considered one of the five cardinal gemstones, alongside diamond, ruby, sapphire, and emerald, until large deposits were found in Brazil in the 19th century.

Field identification & locations

Identified by its purple color and 7-scale hardness. Commonly found in Brazil, Uruguay, South Korea, and Russia. Collectors look for deep saturation and clarity.