sedimentary
Chert
Microcrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, dull to waxy luster, conchoidal fracture, and colors ranging from gray to brown.
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Physical properties
Hardness of 7 on the Mohs scale, dull to waxy luster, conchoidal fracture, and colors ranging from gray to brown.
Formation & geological history
Formed through the chemical precipitation of silica from aqueous solutions or the accumulation of siliceous microfossil skeletal remains in marine environments.
Uses & applications
Historically used for prehistoric stone tools due to its sharp edges when fractured; modern use includes decorative landscaping and abrasives.
Geological facts
Chert nodules are frequently found embedded in limestone or chalk formations worldwide.
Field identification & locations
Identify by its extreme hardness, smooth conchoidal fracture, and waxy appearance. Common in sedimentary deposits globally.
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