sedimentary
Flint
Cryptocrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, dark gray to black color, waxy to vitreous luster, conchoidal fracture with no cleavage.
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Physical properties
Hardness of 7 on the Mohs scale, dark gray to black color, waxy to vitreous luster, conchoidal fracture with no cleavage.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich solutions in marine environments.
Uses & applications
Historically used for making stone tools and fire-starting; currently used for decorative landscaping and historical reenactments.
Geological facts
Flint played a crucial role in human technological development during the Stone Age due to its ability to be chipped into sharp edges.
Field identification & locations
Identified by its distinctive conchoidal fracture, waxy luster, and ability to produce sparks when struck against steel.
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