sedimentary
Agate
Silicon dioxide (Chalcedony), SiO2
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, translucent to opaque transparency, and trigonal crystal system with microcrystalline structure.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, translucent to opaque transparency, and trigonal crystal system with microcrystalline structure.
Formation & geological history
Forms by the deposition of silica from groundwater in the cavities of igneous and sedimentary rocks, often over millions of years.
Uses & applications
Commonly used for ornamental carvings, jewelry, lapidary arts, and scientific instruments due to its durability.
Geological facts
Agates often display distinct concentric banding patterns formed by alternating phases of silica deposition.
Field identification & locations
Identified by its waxy luster, conchoidal fracture, and hardness capable of scratching glass; found worldwide in volcanic cavities.
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