Agate
Image: Brandon Menth (CC BY 3.0)
Mineral NameAgate
Chemical FormulaSiO2
Mohs Hardness6.5
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.6
Colorsreddish-orange, brown, yellow
Transparencytranslucent
Type LocalityWorldwide (e.g., Brazil, Uruguay, Mexico, USA)
Mineral GroupSilicates
Usesjewelry, ornamental objects, collector
Associated Mineralsquartz, calcite, zeolites
Raritycommon
Description
The image displays a collection of small, tumbled or naturally broken pieces of agate, predominantly in shades of reddish-orange and brown, with some lighter yellowish tones, appearing translucent.
Geological Context
Agates typically form in cavities of volcanic rocks, such as basalt, where silica-rich solutions deposit concentric layers of chalcedony. They can also be found in some metamorphic and sedimentary environments.
