sedimentary
Agate Geode
Silicon dioxide (Quartz), SiO2
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy luster, microcrystalline quartz structure, and conchoidal fracture. Colors vary in concentric bands of brown, tan, and white.
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Physical properties
Hardness of 7 on the Mohs scale, waxy luster, microcrystalline quartz structure, and conchoidal fracture. Colors vary in concentric bands of brown, tan, and white.
Formation & geological history
Formed through the deposition of silica-rich groundwater inside gas cavities within volcanic or sedimentary rocks over millions of years.
Uses & applications
Widely used in ornamental carvings, gemstone jewelry, and as highly prized collector specimens.
Geological facts
Geodes start as hollow bubbles in rock where mineral-rich water slowly precipitates microscopic quartz crystals layer by layer.
Field identification & locations
Easily identified by its distinctive exterior nodule shape and hollow interior lined with concentric microcrystalline banding or quartz crystals. Found globally in volcanic deposits.
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