sedimentary
Agate
Silicon dioxide (Chalcedony), SiO2
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy luster, microcrystalline crystal structure, and exhibits distinctive concentric color banding.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy luster, microcrystalline crystal structure, and exhibits distinctive concentric color banding.
Formation & geological history
Formed by the deposition of silica from groundwater in cavities of igneous and sedimentary rocks over millions of years.
Uses & applications
Widely used in ornamental carvings, polished slabs, jewelry, and precision instruments like mortar and pestles.
Geological facts
Agate banding reflects successive stages of silica deposition, creating unique patterns often resembling landscapes or fortifications.
Field identification & locations
Easily identified by its translucent to opaque banded layers and conchoidal fracture; commonly found in volcanic rock cavities worldwide.
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