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, lavender
Transparencytransparent
Type LocalityBrazil, Uruguay, Zambia, Canada
Mineral GroupSilicates (Tectosilicates)
Usesjewelry, ornamental, collector
Associated Mineralscalcite, goethite, hematite, feldspar
Raritycommon
Description
This image displays a cluster of amethyst crystals, exhibiting various shades of purple, from pale lavender to deeper violet, with some areas appearing translucent. The crystals are well-formed, showing typical hexagonal prism faces and pyramidal terminations, growing on a light-colored matrix.
Geological Context
Amethyst forms in hydrothermal veins and cavities within igneous rocks, particularly basaltic lavas, creating geodes. Its characteristic purple color is due to irradiation of iron impurities within the quartz lattice.
