sedimentary
Flint
Cryptocrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, dark gray to brown color, waxy to vitreous luster, and conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, dark gray to 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 and fire-starting; currently used for decorative items and collection.
Geological facts
Flint played a crucial role in human technological development during the Stone Age due to its sharp edges when fractured.
Field identification & locations
Identified by its conchoidal fracture and waxy luster; commonly found embedded in chalk or limestone deposits worldwide.
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