sedimentary
Flint
Cryptocrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, typically brown, gray, or black, with a waxy to vitreous luster and conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, typically brown, gray, or black, with a waxy to vitreous luster and conchoidal fracture.
Formation & geological history
Formed through the chemical replacement of calcium carbonate by silica-rich solutions within chalk or limestone formations.
Uses & applications
Historically used for making stone tools and sparking fire, and currently used for decorative landscaping and industrial ball mills.
Geological facts
Flint has been utilized by humans for over two million years to create sharp-edged cutting tools and weapons.
Field identification & locations
Identify it by its distinct conchoidal fracture and ability to scratch glass; commonly found embedded in chalk deposits worldwide.
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