fossil

Chert (Arrowhead Point)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

AI-generated identification · may be incorrect

Hardness: 6.5-7 Mohs; Color: Tan, beige, or brown with mottling; Luster: Dull to waxy; Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture).

Hardness: 6
Color: Tan, beige, or brown with mottling
Luster: Dull to waxy

Identified July 6, 2026More fossil →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Tan, beige, or brown with mottling; Luster: Dull to waxy; Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture).

Formation & geological history

Formed through the accumulation of silica-rich organic remains or chemical precipitation in sedimentary environments. As an artifact, it was knapped by humans during the Stone Age or later periods.

Uses & applications

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

Geological facts

Chert is favored for stone tools because it fractures predictably in a process called conchoidal fracture, creating very sharp edges.

Field identification & locations

Identified by its triangular or leaf-like worked shape and characteristic flake scars. Commonly found in areas with high limestone concentrations or at known archaeological sites.