Amethyst
Image: <a href="//commons.wikimedia.org/wiki/User:Servitiu" title="User:Servitiu">Eugenio Hansen, OFS</a> (CC BY-SA 3.0)
Mineral NameAmethyst
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorspurple, violet, lavender
Transparencytransparent
Type LocalityBrazil (e.g., Rio Grande do Sul), Uruguay, Zambia
Mineral GroupSilicates
Usesjewelry, collector, decorative
Associated Mineralscalcite, zeolites, agate
Raritycommon
Description
The image displays a large geode or vug lined with countless sparkling, well-formed purple amethyst crystals, ranging from light lavender to deep violet hues.
Geological Context
Amethyst forms in hydrothermal solutions within cavities and geodes in volcanic rocks, particularly basalt flows, where silica-rich fluids deposit quartz crystals. The purple color is caused by trace iron impurities and natural irradiation.
