sedimentary
Chert Arrowhead
Cryptocrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and brownish-grey color.
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Physical properties
Hardness of 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and brownish-grey color.
Formation & geological history
Formed through the replacement of limestone or chalk by microcrystalline silica in marine environments.
Uses & applications
Historically used by indigenous peoples for making tools, weapons, and projectile points.
Geological facts
Chert was widely favored for primitive weaponry due to its sharp edges when fractured.
Field identification & locations
Identified by its conchoidal fracture and lack of visible crystal grains, commonly found near ancient settlement sites.
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