Agate enhydros
Image: <a href="//commons.wikimedia.org/wiki/User:Archaeodontosaurus" title="User:Archaeodontosaurus">Didier Descouens</a> (CC BY-SA 4.0)
Mineral NameAgate enhydros
Chemical FormulaSiO2
Mohs Hardness7
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavagenone
Fractureconchoidal
Specific Gravity2.65
Colorsbrown, tan, dark grey, white
Transparencytranslucent
Type LocalityBrasil
Mineral GroupSilicates
Usesjewelry, ornamental objects, collector
Associated Mineralsquartz, calcite, zeolites
Rarityuncommon
Description
A polished cross-section of an agate nodule, displaying concentric bands of dark grey and white chalcedony, with a rough, tan exterior. It contains a trapped water inclusion (enhydros) visible through the translucent agate.
Geological Context
Agate forms in cavities of volcanic rocks, where silica-rich fluids deposit layers of cryptocrystalline quartz. Enhydros occur when ancient water is trapped within these cavities during the agate's formation.
