mineral
Amethyst Quartz
SiO2 (Silicon Dioxide with Iron impurities)
Hardness: 7 (Mohs scale); Color: Purple, violet, or lavender; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
- Hardness
- 7 (Mohs scale)
- Color
- Purple, violet, or lavender
- Luster
- Vitreous (glass-like)
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Physical properties
Hardness: 7 (Mohs scale); Color: Purple, violet, or lavender; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
Formation & geological history
Formed in hydrothermal veins and basaltic geodes. The purple color is caused by gamma irradiation of trace trivalent iron (Fe3+) in the silica crystal lattice. Often found in volcanic environments ranging from millions to hundreds of millions of years old.
Uses & applications
Primarily used as a gemstone in jewelry, as decorative crystal clusters, and widely collected by mineral enthusiasts for metaphysical or aesthetic purposes.
Geological facts
Amethyst was considered one of the 'Cardinal Gems' until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness.
Field identification & locations
Identify by its purple hue, 6-sided prismatic crystal shape, and its ability to scratch glass. Found commonly in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep saturation of color and clarity.
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