Agate
Image: <a rel="nofollow" class="external text" href="https://web.archive.org/web/20161028042823/http://www.panoramio.com/user/8859301?with_photo_id=132987007">Brandon Menth</a> (CC BY 3.0)
Mineral NameAgate
Chemical FormulaSiO2
Mohs Hardness6.5
Crystal Systemtrigonal
Streak ColorWhite
CleavageNone
FractureConchoidal
Specific Gravity2.65
Colorsorange, brown, cream, white
TransparencyTranslucent
Type LocalityWorldwide, notable localities include Brazil, Uruguay, Mexico, USA (Oregon, Montana), Germany.
Mineral GroupSilicates
Usesjewelry, ornamental objects, lapidary arts, collector's items
Associated Mineralsquartz, calcite, zeolites
Raritycommon
Description
This image displays a polished or tumbled agate, characterized by distinct concentric banding in warm shades of orange, brown, and creamy white, with a translucent quality.
Geological Context
Agate forms in cavities of volcanic rocks (like basalt) or ancient lavas, where silica-rich solutions deposit successive layers of microcrystalline quartz (chalcedony), often filling the void to create geodes or nodules.
