sedimentary

Chert Arrowhead

Cryptocrystalline Quartz (SiO2)

Hardness: 7; Color: Tan to reddish-brown; Luster: Waxy to dull; Crystal structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7
Color: Tan to reddish-brown
Luster: Waxy to dull

Identified June 10, 2026More sedimentary →

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Physical properties

Hardness: 7; Color: Tan to reddish-brown; Luster: Waxy to dull; Crystal structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed as nodules or beds in limestone/chalk through silica replacement; geological age varies. This specimen was anthropogenically worked via flint knapping into a projectile point.

Uses & applications

Historically used for hunting; currently valued as an archaeological artifact and for hobbyist collecting.

Geological facts

Chert was one of the most important minerals for early humans because its conchoidal fracture creates razor-sharp edges. Artifacts like these can be thousands of years old.

Field identification & locations

Identify by the systematic flaking patterns (flake scars) characteristic of tool-making. Commonly found in tilled fields or near water sources in areas with chert-bearing geology.