Amethyst Geode
Image: <a rel="nofollow" class="external text" href="https://www.flickr.com/people/14730981@N08">James Petts</a> from London, England (CC BY-SA 2.0)
Mineral NameAmethyst Geode
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorspurple, violet, lavender, white
Transparencytranslucent
Type LocalityBrazil, Uruguay, Mexico
Mineral GroupSilicates
Usesjewelry, collector, decorative
Associated Mineralsquartz, chalcedony, calcite
Raritycommon
Description
This image shows a detail of an amethyst geode, revealing a cavity lined with numerous small, sparkling purple crystals. The outer shell appears rough and lighter in color, contrasting with the vibrant interior.
Geological Context
Amethyst forms in geodes within volcanic rocks or hydrothermal veins. Silica-rich fluids deposit quartz crystals containing trace amounts of iron, which, upon natural irradiation, develop the characteristic purple color.
