sedimentary
Chert (Flint Flake)
Microcrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness 7 on Mohs scale, earthy to waxy luster, conchoidal fracture, typically tan to brown or gray.
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Physical properties
Hardness 7 on Mohs scale, earthy to waxy luster, conchoidal fracture, typically tan to brown or gray.
Formation & geological history
Formed biochemically or chemically through the precipitation of microcrystalline silica in marine sedimentary environments.
Uses & applications
Historically used for prehistoric stone tools and strike-a-light fire starters; modern uses include construction aggregate and road metal.
Geological facts
Due to its fine-grained structure and predictable conchoidal fracturing, chert was one of the most critical lithic materials used by early humans for tools.
Field identification & locations
Identifiable by its sharp edges, hardness capable of easily scratching glass, and lack of visible cleavage planes; abundant worldwide in limestone formations.
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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