mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Hardness: 7 Mohs; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (often found as prismatic crystals); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
- Hardness
- 7 Mohs
- Color
- Purple, violet, or lavender
- Luster
- Vitreous (glassy)
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 Mohs; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (often found as prismatic crystals); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
Formation & geological history
Formed in hydrothermal veins and cavities (geodes) within igneous rocks. The purple color is caused by gamma irradiation of trivalent iron (Fe3+) impurities within the quartz lattice.
Uses & applications
Primarily used as a gemstone in jewelry (rings, necklaces, earrings), as decorative specimens for collectors, and in metaphysical practices.
Geological facts
Amethyst was considered a precious stone on par with diamonds until large deposits were discovered in Brazil in the 19th century. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.
Field identification & locations
Identify by its characteristic purple color and quartz-like crystal habit. Common in Brazil, Uruguay, Africa, and Canada. Collectors look for deep 'Siberian' purple hues and high transparency.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Schist
Schist
Metamorphic
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock