sedimentary
Flint
Microcrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, typically dark 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 dark gray or black with a waxy to vitreous luster and conchoidal fracture.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich groundwater over millions of years.
Uses & applications
Historically used for making stone tools, weapons, and fire-starting flint-and-steel sets.
Geological facts
Flint produces sparks when struck against steel due to its high hardness and brittle fracture creating sharp edges.
Field identification & locations
Identified by its conchoidal fracture, waxy luster, and ability to scratch glass; commonly found inside chalk formations.
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