mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 on Mohs scale; Color: Purple, violet, Lavender; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal prisms; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
- Hardness
- 7 on Mohs scale
- Color
- Purple, violet, Lavender
- Luster
- Vitreous (glass-like)
Identified More mineral →
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: Purple, violet, Lavender; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal prisms; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
Formation & geological history
Formed in hydrothermal veins or as linings within volcanic rock gas cavities (geodes) when silica-rich water crystallizes over millions of years, typically in Cenozoic era basalt flows.
Uses & applications
Primarily used for jewelry (gemstones), ornamental carvings, crystal healing practices, and as a popular decorative mineral for collectors.
Geological facts
The purple color comes from irradiation of iron impurities within the quartz lattice. It was historically considered as precious as diamonds until large deposits were found in Brazil in the 19th century.
Field identification & locations
Identified by its distinctive purple color and hexagonal crystal points. Major deposits are found in Brazil, Uruguay, and Zambia. Collectors should look for saturated color with minimal inclusions.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock