mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified June 2, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich water precipitates crystals over time. The purple color is caused by irradiation of trivalent iron (Fe3+).

Uses & applications

Primarily used in jewelry, decorative items, and lapidary arts. It is also a popular specimen for mineral collectors and practitioners of crystal healing.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habit. Common locations include Brazil, Uruguay, Zambia, and Canada. Look for crystal faces and glass-like luster in the field.