sedimentary
Flint
Microcrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on Mohs scale, dark gray to black color, waxy to vitreous luster, and conchoidal fracture with no cleavage.
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Physical properties
Hardness of 7 on Mohs scale, dark gray to black color, waxy to vitreous luster, and conchoidal fracture with no cleavage.
Formation & geological history
Formed through the chemical replacement of calcium carbonate in chalk or limestone beds by silica-rich groundwaters over millions of years.
Uses & applications
Historically used for making stone tools, arrowheads, and fire-starting flint-and-steel sets.
Geological facts
Flint is extremely durable and breaks with sharp, razor-like edges, making it essential for ancient human survival and technology.
Field identification & locations
Identify by its waxy luster, conchoidal fracture, and ability to scratch glass; commonly found embedded in chalk formations worldwide.
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