sedimentary
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Hardness: 7 (Mohs scale), Color: tan to grayish-brown with banding, Luster: waxy to dull, Crystal Structure: Cryptocrystalline, Cleavage: None (conchoidal fracture)
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Physical properties
Hardness: 7 (Mohs scale), Color: tan to grayish-brown with banding, Luster: waxy to dull, Crystal Structure: Cryptocrystalline, Cleavage: None (conchoidal fracture)
Formation & geological history
Formed via the accumulation of silica-rich organic remains or chemical precipitation in marine environments. This specimen was anthropogenically worked via knapping from sedimentary chert nodules.
Uses & applications
Historically used for hunting and tools. Currently valued as an archaeological artifact and for educational or private collections.
Geological facts
Chert and flint were the primary materials for human tools for millions of years due to their ability to produce a razor-sharp edge when fractured.
Field identification & locations
Identified by its triangular shape, side notches, and characteristic flaking (scars) from pressure knapping. Common in regions with sedimentary limestone deposits.
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