sedimentary
Tumbled Agate
Silicon Dioxide (Chalcedony), SiO2
AI-generated identification · may be incorrectHardness of 6.5-7 on the Mohs scale, waxy luster, conchoidal fracture, and cryptocrystalline structure. Colors vary widely due to impurities, often showing concentric banding.
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Physical properties
Hardness of 6.5-7 on the Mohs scale, waxy luster, conchoidal fracture, and cryptocrystalline structure. Colors vary widely due to impurities, often showing concentric 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
Used primarily in lapidary arts, jewelry, as tumbled pocket stones, and for ornamental carvings.
Geological facts
Agate was highly prized in ancient civilizations as a talisman and for making intaglio seals. It is the mystic birthstone for the sign of Gemini.
Field identification & locations
Identified by its microcrystalline texture, hardness, and distinct banding patterns. Commonly found worldwide in volcanic rock cavities.
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