gemstone
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 on Mohs scale. Color: Deep violet-purple to pale lavender. Luster: Vitreous. Crystal system: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.
- Hardness
- 7 on Mohs scale
- Color
- Deep violet-purple to pale lavender
- Luster
- Vitreous
Identified More gemstone →
Explore Amethyst in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale. Color: Deep violet-purple to pale lavender. Luster: Vitreous. Crystal system: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.
Formation & geological history
Forms inside basaltic or granitic geodes and hydrothermally altered rock veins when iron-bearing silica solutions precipitate and are exposed to natural gamma radiation.
Uses & applications
Popular in fine and fashion jewelry (rings, necklaces, earrings), ornamental carvings, and gemstone collections.
Geological facts
Amethyst is the official birthstone for February and the traditional gift for the 6th wedding anniversary. Ancient Greeks believed it prevented drunkenness and named it after 'amethystos' meaning 'not intoxicated'.
Field identification & locations
Identified by its distinctive purple coloration, hardness of 7, and glass-like vitreous luster. Commonly mined in Brazil, Uruguay, Madagascar, Zambia, and Russia.
More like this
Other gemstone specimens
Diamond and Gold Jewelry
Carbon (Diamond) / Au (Gold)
gemstone
Ammolite
Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)
mineral
Cubic Zirconia (simulant) or Diamond
ZrO2 (Cubic Zirconia) or C (Diamond)
gemstone
Black Opal Ring (Carved Opal)
Hydrated Silicon Dioxide (SiO2·nH2O)
gemstone
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
Cubic Zirconia (or possibly Diamond)
Zirconium dioxide (or Carbon)
gemstone