sedimentary
Flint
Cryptocrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and typically brown, grey, or black in color.
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Physical properties
Hardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and typically brown, grey, or black in color.
Formation & geological history
Formed through the replacement of calcium carbonate by silica in chalk or limestone formations during the Cretaceous period.
Uses & applications
Historically used for making stone tools and sparking fire, and currently used in ceramics and abrasive materials.
Geological facts
Flint fractures to create extremely sharp edges, making it the premier material for prehistoric projectile points and blades.
Field identification & locations
Identified by its conchoidal fracture, waxy feel, and ability to scratch glass. Found worldwide in chalk deposits.
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