gemstone
Amethyst
Quartz (Silicon Dioxide, SiO2)
Hardness: 7 on the Mohs scale. Color: Light to dark purple or violet. Luster: Vitreous (glass-like). Crystal structure: Trigonal (hexagonal system). Cleavage: None (conchoidal fracture). Specific gravity: 2.65.
- Hardness
- 7 on the Mohs scale
- Color
- Light to dark purple or violet
- Luster
- Vitreous (glass-like)
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Physical properties
Hardness: 7 on the Mohs scale. Color: Light to dark purple or violet. Luster: Vitreous (glass-like). Crystal structure: Trigonal (hexagonal system). Cleavage: None (conchoidal fracture). Specific gravity: 2.65.
Formation & geological history
Formed in hydrothermal veins and gas cavities (vugs/geodes) in volcanic rocks, where silica-rich solutions cool and crystallize over millions of years.
Uses & applications
Widely used in jewelry, ornamental carvings, crystal healing, and mineral collecting.
Geological facts
Amethyst was once considered as valuable as diamond, ruby, and emerald until large deposits were discovered in Brazil. Its purple color comes from iron impurities combined with natural irradiation.
Field identification & locations
Easily identified by its distinctive purple color and standard hexagonal crystal form with pyramidal terminations. Found globally, with notable deposits in Brazil, Uruguay, Zambia, and the USA.
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