sedimentary
Fossiliferous Chert
Microcrystalline quartz with fossil inclusions (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, beige to tan color, waxy luster, amorphous crystal structure with conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, beige to tan color, waxy luster, amorphous crystal structure with conchoidal fracture.
Formation & geological history
Formed through the replacement of limestone or accumulation of siliceous skeletal remains in marine environments over millions of years.
Uses & applications
Used historically for stone tools and occasionally as a decorative lapidary stone.
Geological facts
This specimen contains a distinct rectangular crinoid columnal or fossil mold imprint on its surface.
Field identification & locations
Identify by its high hardness, waxy luster, and embedded microfossils; commonly found in ancient marine limestone deposits and river gravels.
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