sedimentary
Agate Nodule
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 6.5 to 7 on the Mohs scale, waxy luster, conchoidal fracture, and cryptocrystalline structure showing banded patterns.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, waxy luster, conchoidal fracture, and cryptocrystalline structure showing banded patterns.
Formation & geological history
Formed through the deposition of silica-rich groundwater in cavities of volcanic or sedimentary rocks over millions of years.
Uses & applications
Used primarily in lapidary arts, ornamental carvings, jewelry making, and as mineral specimens for collectors.
Geological facts
Agate nodules often form in gas cavities within ancient volcanic lavas, later lined or filled with microcrystalline quartz.
Field identification & locations
Identify in the field by its characteristic weathered outer skin and concentric banding when fractured; commonly found globally in volcanic regions.
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Sedimentary limestone with invertebrate fossil imprint
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Sandstone or Siltstone
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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