sedimentary
Chert Arrowhead
Cryptocrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, dull to vitreous luster, conchoidal fracture, and brownish-grey color.
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Physical properties
Hardness of 7 on the Mohs scale, dull to vitreous luster, conchoidal fracture, and brownish-grey color.
Formation & geological history
Formed through the diagenesis of silica-rich marine sediments over millions of years, later shaped by human flaking.
Uses & applications
Historically used for hunting and cutting tools; now a prized artifact for collectors and archaeological study.
Geological facts
Chert was widely favored by prehistoric humans due to its predictable conchoidal fracture, allowing fine control during knapping.
Field identification & locations
Identify by its sharp, pressure-flaked edges and waxy luster; commonly found in agricultural fields and ancient campsites.
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