mineral

Amethyst (Tumbled Stone)

Amethyst (Silicon Dioxide with Iron impurities, SiO2)

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

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

Identified April 24, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. The purple color comes from irradiation, iron impurities, and the presence of trace elements. It is often found in volcanic rock cavities.

Uses & applications

Commonly used in jewelry (faceting, cabochons), crystal healing/spiritual practices, and as decorative tumbled stones for collectors.

Geological facts

Amethyst was considered as valuable as diamonds until large deposits were found in Brazil in the 19th century. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its distinctive purple color and lack of cleavage. In the field, look for hexagonal crystal points inside hollow geodes. Commonly found in Brazil, Uruguay, and Zambia.

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