sedimentary
Flint
Cryptocrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on Mohs scale, typically dark gray or black with a waxy luster and conchoidal fracture.
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Physical properties
Hardness of 7 on Mohs scale, typically dark gray or black with a waxy luster and conchoidal fracture.
Formation & geological history
Formed through the replacement of calcium carbonate by silica-rich solutions in chalk or limestone during the Cretaceous period.
Uses & applications
Historically used for making stone tools and striking fire; currently used in abrasives and ceramics.
Geological facts
Flint played a critical role in human technological evolution during the Stone Age due to its ability to be chipped into extremely sharp edges.
Field identification & locations
Identified by its conchoidal fracture and capacity to produce sparks when struck against steel. Commonly found in chalk deposits worldwide.
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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