mineral
Amethyst
Amethyst (Silicon Dioxide, SiO2 with Iron impurities)
Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.
- Hardness
- 7 on Mohs scale
- Color
- Purple to violet
- Luster
- Vitreous (glassy)
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Physical properties
Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.
Formation & geological history
Formed in igneous and hydrothermal environments, typically as linings within geodes or in veins. The purple color comes from irradiation of iron impurities within the quartz structure. Most specimens range from late Mesozoic to Cenozoic eras.
Uses & applications
Primarily used as a semi-precious gemstone in jewelry, for ornamental carvings, and as a popular mineral specimen for collectors. It is also used in crystal healing practices.
Geological facts
Amethyst is the birthstone for February. The name comes from the ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness.
Field identification & locations
Identify in the field by its distinct purple color, hexagonal crystal shape (if terminating), and ability to scratch glass (hardness 7). Commonly found in Brazil, Uruguay, and parts of Africa.
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Mineral
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