mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 on Mohs scale; Color: Deep purple to violet; Luster: Vitreous/glassy when polished; Crystal System: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
- Hardness
- 7 on Mohs scale
- Color
- Deep purple to violet
- Luster
- Vitreous/glassy when polished
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Physical properties
Hardness: 7 on Mohs scale; Color: Deep purple to violet; Luster: Vitreous/glassy when polished; Crystal System: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
Formation & geological history
Forms primarily inside hydrothermal veins and volcanic geodes where silica-rich fluids cool under specific pressure and chemical conditions, with gamma irradiation imparting the characteristic purple hue to trace iron content.
Uses & applications
Extensively used in jewelry, lapidary arts, decorative items, tumbled stones, and metaphysical collections.
Geological facts
Amethyst is the official birthstone for February. The name comes from the ancient Greek word 'amethystos', which translates to 'not intoxicated', as the Greeks believed it protected the owner from drunkenness.
Field identification & locations
Identified by its rich violet-purple coloration, hardness of 7 (scratches glass), and glassy luster. Commonly found in Brazil, Uruguay, Madagascar, Zambia, and Russia. Small tumbled pieces are widely available.
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