sedimentary
Flint
SiO2 (Microcrystalline Quartz)
AI-generated identification · may be incorrectHardness of 7 on Mohs scale, concoidal fracture, waxy to vitreous luster, and brownish-grey color.
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Physical properties
Hardness of 7 on Mohs scale, concoidal fracture, waxy to vitreous luster, and brownish-grey color.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich groundwaters during the Cretaceous period.
Uses & applications
Historically used for making stone tools and fire-starting; currently utilized in landscaping and road aggregates.
Geological facts
Prehistoric humans heavily favored flint for knapping sharp cutting edges and arrowheads due to its predictable conchoidal fracture.
Field identification & locations
Easily identified by its distinctive conchoidal fracture, sharp edges, and waxy luster; commonly found embedded in chalk deposits worldwide.
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