sedimentary
Chert Arrowhead
Microcrystalline Quartz (SiO2)
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
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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.
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