sedimentary
Chert
Microcrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and colors ranging from gray to brown.
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Physical properties
Hardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and colors ranging from gray to brown.
Formation & geological history
Formed through the chemical precipitation of silica-rich fluids or accumulation of siliceous skeletal remains in marine environments.
Uses & applications
Historically used for making stone tools and weapons due to its sharp edges when fractured.
Geological facts
Chert is exceptionally durable and resistant to weathering, often surviving long after surrounding limestone erodes away.
Field identification & locations
Identified easily by its conchoidal fracture and high hardness. Commonly found nodules within limestone formations globally.
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