sedimentary
Flint
Cryptocrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, dark gray to black color, waxy to vitreous luster, conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, dark gray to black color, waxy to vitreous luster, conchoidal fracture.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich solutions in marine environments over millions of years.
Uses & applications
Historically used for making stone tools and fire-starting, and currently used in abrasives, ceramics, and decorative items.
Geological facts
Prehistoric humans heavily favored flint for knapping sharp cutting edges and arrowheads due to its predictable conchoidal fracture.
Field identification & locations
Identify by its dark color, waxy luster, and sharp conchoidal edges; commonly found embedded in chalk and limestone deposits worldwide.
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