sedimentary
Agate
Silicon Dioxide (Chalcedony), SiO2
AI-generated identification · may be incorrectHardness of 6.5-7 on the Mohs scale, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture, and specific gravity around 2.6.
Identified More sedimentary →
Explore Agate in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 6.5-7 on the Mohs scale, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture, and specific gravity around 2.6.
Formation & geological history
Formed by the deposition of silica-rich groundwater in cavities of igneous or sedimentary rocks, typically over millions of years.
Uses & applications
Widely used in ornamental carvings, jewelry, decorative objects, and precision laboratory instruments.
Geological facts
Agate bands record ancient environmental conditions and fluid chemistry changes during the crystal growth process.
Field identification & locations
Identify by its distinctive concentric banding and waxy luster; commonly found globally in volcanic rock cavities and river gravels.
More like this
Other sedimentary specimens
Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone
Arenite
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary