sedimentary
Chert / Flint Tool
Cryptocrystalline quartz (SiO2)
Hardness of 7 on the Mohs scale, dull to waxy luster, conchoidal fracture, opaque to translucent, brown to dark gray color, specific gravity around 2.60 to 2.65.
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Physical properties
Hardness of 7 on the Mohs scale, dull to waxy luster, conchoidal fracture, opaque to translucent, brown to dark gray color, specific gravity around 2.60 to 2.65.
Formation & geological history
Formed through the chemical precipitation of silica in marine environments, often replacing carbonate rocks like limestone over millions of years.
Uses & applications
Historically used by ancient humans for making stone tools, arrowheads, and blades due to its sharp conchoidal fracture; currently collected as an artifact or geological specimen.
Geological facts
This specimen appears to be an intentionally flaked lithic artifact, possibly a hand axe, biface, or projectile point preform fashioned by early humans.
Field identification & locations
Identified by its pointed shape, intentional percussion flake scars, and the sharp edges characteristic of human knapping. Commonly found near ancient campsites and river terraces.
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