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, conchoidal fracture, and cryptocrystalline crystal structure with distinctive banded coloration.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and cryptocrystalline crystal structure with distinctive banded coloration.
Formation & geological history
Formed through the deposition of silica from groundwater in cavities of ancient volcanic or sedimentary rocks, often over millions of years.
Uses & applications
Widely used in ornamental carvings, jewelry, lapidary art, and as a popular specimen for mineral collectors.
Geological facts
Agate was highly prized in antiquity for signet rings and talismans due to its resistance to acids and durability.
Field identification & locations
Identify by its waxy luster, microcrystalline banding, and hardness that scratches glass. Common worldwide, especially in volcanic regions.
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Fossiliferous Sedimentary Rock
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