Agate
Image: <a href="//commons.wikimedia.org/wiki/User:SKas" title="User:SKas">SKas</a> (CC BY-SA 4.0)
Mineral NameAgate
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lusterwaxy
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.6
Colorspale green, dark green, gray, off-white, pale brown
Transparencytranslucent
Type LocalityFar East of the Russian Federation
Mineral GroupSilicates
Usesjewelry, ornamental objects, collector's item
Associated Mineralsquartz
Raritycommon
Description
This image displays a polished cross-section of a banded agate concretion, featuring concentric layers of pale green, gray, and off-white chalcedony, with a central geode containing small quartz crystals.
Geological Context
Agate typically forms in cavities within volcanic rocks or as concretions in sedimentary environments, where silica-rich solutions deposit successive layers of microcrystalline quartz, often with a central void forming a geode.
