sedimentary

Chert Arrowhead

Cryptocrystalline microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 7; Color: Grayish-brown; Luster: Waxy to dull; Crystal structure: Trigonal (microscopic); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7
Color: Grayish-brown
Luster: Waxy to dull

Identified July 6, 2026More sedimentary →

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Physical properties

Hardness: 7; Color: Grayish-brown; Luster: Waxy to dull; Crystal structure: Trigonal (microscopic); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formation occurs as nodules or beds in limestone or chalk through chemical precipitation of silica. This specimen has been anthropogenically modified through flint knapping. Age can range from millions of years for the stone to thousands of years for the artifact.

Uses & applications

Historically used for hunting and tools; currently valued as an archaeological artifact and collector's item.

Geological facts

Arrowheads are technically projectile points. Chert was favored by ancient peoples because its conchoidal fracture allows for the creation of extremely sharp, durable edges.

Field identification & locations

Identified by the distinct flaking patterns (scars) from the knapping process and its triangular, notched shape. Commonly found in areas with high limestone concentrations or ancient habitation sites.