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, microcrystalline crystal structure, conchoidal fracture with distinct translucent banding.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy to vitreous luster, microcrystalline crystal structure, conchoidal fracture with distinct translucent banding.
Formation & geological history
Formed by the deposition of silica from groundwater in cavities of ancient volcanic and sedimentary rocks over millions of years.
Uses & applications
Widely used in ornamental jewelry, decorative carvings, tumbled stones, and precision laboratory instruments.
Geological facts
Agate bands represent successive layers of microscopic quartz crystals filling hollow cavities left by volcanic gas bubbles.
Field identification & locations
Identified by its characteristic concentric color bands and waxy sheen; commonly found in volcanic regions worldwide.
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