sedimentary

Chert Arrowhead

Chert (Cryptocrystalline variety of Quartz, SiO2)

AI-generated identification · may be incorrect

Hardness: 7 Mohs; Color: Grayish-brown; Luster: Waxy to dull; Structure: Cryptocrystalline; Fracture: Conchoidal (shell-like curves); Opaque to translucent edges.

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

Identified July 19, 2026More sedimentary →

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Physical properties

Hardness: 7 Mohs; Color: Grayish-brown; Luster: Waxy to dull; Structure: Cryptocrystalline; Fracture: Conchoidal (shell-like curves); Opaque to translucent edges.

Formation & geological history

Formed through the accumulation of silica-rich organic remains or chemical precipitation in marine environments, subsequently shaped by humans (lithic reduction/knapping) during the prehistoric era.

Uses & applications

Historically used as projectile points for hunting or tools for cutting and scraping; today valued as archaeological artifacts and collectibles.

Geological facts

This specimen is a cultural artifact made from stone. Chert is a preferred material for stone tools because its conchoidal fracture produces extremely sharp edges, similar to glass.

Field identification & locations

Identified by the tell-tale 'flake scars' from percussion and pressure flaking. Found in fields, near ancient water sources, or in sedimentary outcrops. Collectors look for symmetry and retouching along the edges.