sedimentary
Flint
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectMohs hardness of 7, dark brown to black color, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture.
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Physical properties
Mohs hardness of 7, dark brown to black color, waxy to vitreous luster, cryptocrystalline structure, conchoidal fracture.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich groundwater over millions of years.
Uses & applications
Historically used for making stone tools and fire-starting; today popular among collectors and survivalists.
Geological facts
Flint played a critical role in human technological evolution during the Stone Age due to its sharp conchoidal fracture.
Field identification & locations
Identified by its waxy luster, conchoidal fracture, and ability to spark when struck with steel. Commonly found in chalk deposits worldwide.
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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