sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 7 on Mohs scale, microcrystalline quartz, smooth waxy to dull luster, sharp conchoidal fracture, opaque to translucent, tan/brownish color.
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Physical properties
Hardness of 7 on Mohs scale, microcrystalline quartz, smooth waxy to dull luster, sharp conchoidal fracture, opaque to translucent, tan/brownish color.
Formation & geological history
Formed through biochemical sedimentary processes or chemical precipitation from silica-rich fluids replacing limestone or chalk beds.
Uses & applications
Historically used for making stone tools and starting fires due to sparks generated against steel. Used today in flint knapping, gravel, and decorative stone collecting.
Geological facts
Chert fracture patterns produce razor-sharp edges, making it a critical toolmaking resource for prehistoric humans worldwide.
Field identification & locations
Identify in the field by its distinct waxy texture, lack of cleavage, extreme hardness (scratches glass easily), and curved conchoidal fracture edges. Found abundantly in sedimentary formations and stream beds.
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