sedimentary
Chert Arrowhead
Cryptocrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness: 7; Color: Gray to brownish; Lustre: Waxy to vitreous; Crystal Structure: Trigonal/Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
- Hardness
- 7
- Color
- Gray to brownish
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Physical properties
Hardness: 7; Color: Gray to brownish; Lustre: Waxy to vitreous; Crystal Structure: Trigonal/Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65
Formation & geological history
Formed through the accumulation of silica-rich organic remains or chemical precipitation in sedimentary basins. This specific specimen was later anthropocenically modified through pressure flaking.
Uses & applications
Historically used as a hunting projectile or tool; currently a valuable archaeological artifact and collectible.
Geological facts
Chert was highly prized by prehistoric humans because its conchoidal fracture creates edges sharper than a steel scalpel. The technique of making these is called flintknapping.
Field identification & locations
Identify by the systematic flaking patterns (flake scars) along the edges and its characteristic triangular shape. Commonly found in areas with historic indigenous activity and limestone outcrops.
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