sedimentary
Chert Arrowhead
Chert (Cryptocrystalline variety of Quartz, SiO2)
Hardness: 7 Mohs; Color: Grayish-brown; Luster: Waxy to dull; Structure: Cryptocrystalline; Fracture: Conchoidal (shell-like curves); Opaque to translucent edges.
- Hardness
- 7 Mohs
- Color
- Grayish-brown
- Luster
- Waxy to dull
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Physical properties
Hardness: 7 Mohs; Color: Grayish-brown; Luster: Waxy to dull; Structure: Cryptocrystalline; Fracture: Conchoidal (shell-like curves); Opaque to translucent edges.
Formation & geological history
Formed through the accumulation of silica-rich organic remains or chemical precipitation in marine environments, subsequently shaped by humans (lithic reduction/knapping) during the prehistoric era.
Uses & applications
Historically used as projectile points for hunting or tools for cutting and scraping; today valued as archaeological artifacts and collectibles.
Geological facts
This specimen is a cultural artifact made from stone. Chert is a preferred material for stone tools because its conchoidal fracture produces extremely sharp edges, similar to glass.
Field identification & locations
Identified by the tell-tale 'flake scars' from percussion and pressure flaking. Found in fields, near ancient water sources, or in sedimentary outcrops. Collectors look for symmetry and retouching along the edges.
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