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 via the accumulation of siliceous microfossil remains or the chemical replacement of limestone during the Phanerozoic eon.
Uses & applications
Historically used for making stone tools and arrowheads due to its sharp conchoidal fracture.
Geological facts
Chert forms nodules or layers within sedimentary rocks like chalk and limestone. Varieties include flint and jasper.
Field identification & locations
Identified by its high hardness, smooth waxy appearance, and sharp edges when broken; found globally in marine sedimentary sequences.
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Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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