sedimentary
Flint
Cryptocrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, dark gray or brown color, waxy to vitreous luster, and conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, dark gray or brown color, waxy to vitreous luster, and 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, arrowheads, and fire-starting flint-locks; currently collected as a geological specimen.
Geological facts
Flint is extremely durable and breaks with sharp, razor-like edges, making it essential for ancient human survival and toolmaking.
Field identification & locations
Identified by its waxy luster, conchoidal fracture, and ability to spark when struck against steel. Found globally within chalk and limestone formations.
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