
Worked flint (chert) flake or tool
Microcrystalline quartz (SiO₂), commonly called flint or chert
AI-generated identification · may be incorrectHardness about 7 Mohs; opaque tan, gray, and reddish-brown with waxy to dull luster. Very fine-grained cryptocrystalline quartz lacks visible crystals and has conchoidal fracture; the sharp flaked edges and percussion scars indicate intentional knapping.
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