sedimentary
Chert Nodule
Microcrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, earthy to waxy luster, conchoidal fracture, colors range from brown to grey.
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Physical properties
Hardness of 7 on the Mohs scale, earthy to waxy luster, conchoidal fracture, colors range from brown to grey.
Formation & geological history
Formed through the replacement of limestone or chalk by silica-rich groundwater during deep burial and diagenesis.
Uses & applications
Historically used for making stone tools and arrowheads due to its sharp conchoidal fracture.
Geological facts
Chert nodes often form symmetrically inside carbonate host rocks and weather out as resistant nodules.
Field identification & locations
Identify by its extreme hardness, conchoidal fracture, and waxy luster; commonly found in limestone formations worldwide.
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