sedimentary

Chert Arrowhead

Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Dark green to grey; Luster: Waxy to vitreous; Crystal Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Dark green to grey
Luster: Waxy to vitreous

Identified May 3, 2026More sedimentary →

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Physical properties

Hardness: 7 on Mohs scale; Color: Dark green to grey; Luster: Waxy to vitreous; Crystal Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed via the accumulation of silica-rich microfossils or chemical precipitation in sedimentary basins. This specimen has been anthropogenically modified through knapping (flaking) to create a stone tool.

Uses & applications

Historically used for hunting (projectile points) and cutting tools; currently valued as archaeological artifacts and collectibles.

Geological facts

Chert and flint were among the first materials used by early humans to manufacture tools due to their ability to produce extremely sharp edges when fractured.

Field identification & locations

Identified by sharp, flaked edges (scars) and characteristic conchoidal fracture patterns. Found in archaeological sites, stream beds, or areas with exposed limestone or chalk deposits.