sedimentary
Chert (Arrowhead)
Chert (SiO2)
AI-generated identification · may be incorrectHardness: 6.5-7. Color: Grey to brownish-grey. Luster: Waxy to dull. Crystal structure: Cryptocrystalline. Cleavage: None (conchoidal fracture). Specific gravity: 2.6.
- Hardness
- 6
- Color
- Grey to brownish-grey
- Luster
- Waxy to dull
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Physical properties
Hardness: 6.5-7. Color: Grey to brownish-grey. Luster: Waxy to dull. Crystal structure: Cryptocrystalline. Cleavage: None (conchoidal fracture). Specific gravity: 2.6.
Formation & geological history
Formed as microcrystalline quartz aggregates in sedimentary environments, often replacing carbonate material. This specimen has been anthropogenically worked through pressure flaking.
Uses & applications
Historically used for projectile points, scrapers, and blades. Currently of high archaeological and collector value.
Geological facts
This specimen is a lithic artifact (arrowhead or projectile point). Chert was the primary material for prehistoric tools due to its predictable conchoidal fracturing and razor-sharp edges.
Field identification & locations
Identify by the systematic flake scars and serrated edges. Found in areas with limestone outcroppings or historical human settlements. Collectors should note provenance (find location) for ethical/legal reasons.
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