mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 (Mohs scale); Color: Purple, violet, mauve; Luster: Vitreous/glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.
- Hardness
- 7 (Mohs scale)
- Color
- Purple, violet, mauve
- Luster
- Vitreous/glassy
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Physical properties
Hardness: 7 (Mohs scale); Color: Purple, violet, mauve; Luster: Vitreous/glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.
Formation & geological history
Formed in hydrothermal veins and volcanic geodes when silica-rich water deposits crystals inside cavities. The purple color comes from irradiation of iron impurities within the quartz crystal lattice.
Uses & applications
Primarily used as a gemstone in jewelry (rings, necklaces, earrings) and as decorative specimens for collectors or home decor.
Geological facts
Amethyst is the birthstone for February. Its 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 color and glassy luster. It can be found worldwide, with major deposits in Brazil, Uruguay, Zambia, and Canada. Look for hexagonal crystal points or purple pebbles in riverbeds near volcanic regions.
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