Amethyst
Image: “Jon Zander (<a href="//commons.wikimedia.org/wiki/User:Digon3" title="User:Digon3">Digon3</a>)" (CC BY-SA 3.0)
Mineral NameAmethyst
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone (or very poor/indistinct)
Fractureconchoidal
Specific Gravity2.65
Colorspurple, violet
Transparencytransparent
Type LocalityBrazil, Uruguay, Zambia, Russia
Mineral GroupSilicates (Tectosilicates)
Usesjewelry, ornamental, collector, decorative
Associated Mineralscalcite, chalcedony, goethite, hematite
Raritycommon
Description
This image displays a cluster of amethyst crystals, exhibiting a range of purple hues from pale lavender to deeper violet. The crystals are well-formed, showing typical hexagonal prism faces terminating in pyramidal forms, and appear translucent.
Geological Context
Amethyst forms in hydrothermal veins, geodes, and cavities within igneous rocks, particularly basaltic lavas. Its characteristic purple color is due to irradiation and trace amounts of iron impurities within the quartz lattice.
