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 grey to brown.
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Physical properties
Hardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and colors ranging from grey to brown.
Formation & geological history
Formed through the chemical precipitation of silica from seawater or the replacement of limestone during diagenesis.
Uses & applications
Historically used for making stone tools and weapons, and currently used in abrasives and road construction.
Geological facts
Chert fractures easily into extremely sharp edges, making it ideal for prehistoric flintknapping.
Field identification & locations
Identified by its hard, glass-like composition and distinct conchoidal fracture, commonly found within limestone formations worldwide.
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Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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