mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 on Mohs scale; Color: Deep purple to violet; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
- Hardness
- 7 on Mohs scale
- Color
- Deep purple to violet
- Luster
- Vitreous (glass-like)
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Physical properties
Hardness: 7 on Mohs scale; Color: Deep purple to violet; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
Formation & geological history
Formed inside hydrothermal veins, geodes, and cavities in igneous rocks through the precipitation of silica-rich solutions under low-temperature conditions.
Uses & applications
Widely used as a gemstone in jewelry, ornamental carvings, crystal healing practices, and mineral collection.
Geological facts
The deep purple color comes from irradiation of trace amounts of trivalent iron (Fe3+) in the crystal structure. Ancient Greeks believed amethyst could prevent drunkenness.
Field identification & locations
Identified by its distinctive purple color, hardness (scratches glass, cannot be scratched by steel), and conchoidal fracture. Commonly found in Brazil, Uruguay, Zambia, Madagascar, and Russia.
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