sedimentary

Chert Arrowhead

Cryptocrystalline Quartz (SiO2)

Hardness: 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

Identified July 17, 2026More sedimentary →

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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.