mineral
Amethyst
Amethyst (Silicon Dioxide, SiO2 with Iron impurities)
Hardness: 7 (Mohs scale); Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65
- Hardness
- 7 (Mohs scale)
- 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 scale); Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65
Formation & geological history
Formed in hydrothermal veins or as linings in volcanic geodes. The purple color is caused by natural irradiation of trace iron impurities replacing silicon in the quartz lattice. Most commercial amethyst is found in Cenozoic era basalt flows.
Uses & applications
Predominantly used as a gemstone in jewelry, for decorative carvings, and in metaphysical/collecting markets. Historically used for amulets.
Geological facts
In Ancient Greek, 'amethystos' means 'not drunken'; it was believed to prevent intoxication. It is the official birthstone for February and is often found in the royal crown jewels of several nations.
Field identification & locations
Identify by its characteristic purple color and quartz-like fracture. Often found in South America (Brazil, Uruguay) and parts of Africa. For collectors, look for deep, uniform color (Deep Siberian) with minimal visible inclusions.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock
Granite
Granite (Phaneritic intrusive igneous rock)
igneous