gemstone
Amethyst
Silicon Dioxide (SiO2 with iron impurities)
Hardness: 7 on Mohs scale. Color: Deep violet to light lavender. Luster: Vitreous/glassy. Crystal system: Trigonal. Cleavage: None, conchoidal fracture.
- Hardness
- 7 on Mohs scale
- Color
- Deep violet to light lavender
- Luster
- Vitreous/glassy
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Physical properties
Hardness: 7 on Mohs scale. Color: Deep violet to light lavender. Luster: Vitreous/glassy. Crystal system: Trigonal. Cleavage: None, conchoidal fracture.
Formation & geological history
Forms in hydrothermal veins and cavities (geodes) within volcanic rocks when silica-rich fluids cool and crystallize in the presence of trace iron atoms exposed to natural irradiation.
Uses & applications
Widely used in jewelry, decorative carvings, metaphysical practices, and gemstone collections.
Geological facts
Historically, ancient Greeks believed amethyst could prevent drunkenness. It is the official birthstone for February.
Field identification & locations
Identify by its distinct purple hue, glass-like luster, ability to scratch glass (Mohs 7), and lack of cleavage. Commonly found in Brazil, Uruguay, Madagascar, and Zambia.
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