Agate
Image: “Jon Zander (<a href="//commons.wikimedia.org/wiki/User:Digon3" title="User:Digon3">Digon3</a>)” (CC BY-SA 3.0)
Mineral NameAgate
Chemical FormulaSiO2
Mohs Hardness7
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorswhite, grey, brown, reddish-brown, orange
Transparencytranslucent
Type LocalityBrazil, Uruguay, Mexico, USA
Mineral GroupSilicates
Usesjewelry, ornamental objects, collector
Associated Mineralsquartz, zeolites, calcite
Raritycommon
Description
A polished, teardrop-shaped slice of agate displaying distinct concentric bands of white, grey, brown, and reddish-brown hues.
Geological Context
Agate forms in cavities of volcanic rocks or ancient lavas, where silica-rich fluids deposit layers of chalcedony over time, creating its characteristic banding.
