Amethyst
Image: <a href="//commons.wikimedia.org/wiki/User:PumpkinSky" title="User:PumpkinSky">PumpkinSky</a> (CC BY-SA 3.0)
Mineral NameAmethyst
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorspurple, violet
Transparencytranslucent
Type LocalityVirginia, USA
Mineral GroupSilicates
Usesjewelry, collector, ornamental
Associated Mineralsquartz, calcite, feldspar, goethite
Raritycommon
Description
A macro image of a rough, translucent, purple triangular amethyst specimen, showing varying shades of violet.
Geological Context
Amethyst forms in hydrothermal veins and geodes within volcanic rocks, as well as in pegmatites and certain metamorphic rocks, crystallizing from silica-rich fluids.
