mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 on Mohs scale. Color: Light to deep purple, violet. Luster: Vitreous/glassy. Crystal structure: Hexagonal/trigonal quartz. Cleavage: None, conchoidal fracture.
- Hardness
- 7 on Mohs scale
- Color
- Light to deep purple, violet
- Luster
- Vitreous/glassy
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Physical properties
Hardness: 7 on Mohs scale. Color: Light to deep purple, violet. Luster: Vitreous/glassy. Crystal structure: Hexagonal/trigonal quartz. Cleavage: None, conchoidal fracture.
Formation & geological history
Formed in hydrothermal veins and basaltic geodes through volcanic activity, where silica-rich fluids crystallized under heat and pressure with trace amounts of iron exposed to natural irradiation.
Uses & applications
Used extensively in gemstone jewelry, tumbling, lapidary arts, decorative specimens, and metaphysical collection.
Geological facts
Amethyst's purple color comes from irradiation of trace iron impurities within the quartz crystal lattice. Historically, ancient Greeks believed amethyst could prevent intoxication.
Field identification & locations
Identify by its characteristic purple color, hardness (scratches glass), and glassy luster. Commonly found in Brazil, Uruguay, Zambia, Madagascar, and North Carolina, USA.
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