mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple to violet variations; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple to violet variations
Luster: Vitreous (glassy)

Identified March 11, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple to violet variations; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or inside igneous volcanic cavities (geodes). The purple color is caused by natural irradiation and the presence of trace iron replacing silicon in the quartz lattice.

Uses & applications

Primary use is in jewelry (faceted or cabochon), ornamental carvings, and as decorative mineral specimens for collectors.

Geological facts

Amethyst was considered one of the 'Cardinal Gems' until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief it protected its owner from drunkenness.

Field identification & locations

Identify by its distinctive purple hue and hexagonal crystal habits. Common locations include Brazil, Uruguay, Madagascar, and Russia. Collectors should look for deep 'Siberian' purple hues and high clarity.

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