sedimentary
Chert Arrowhead (Projectile Point)
Microcrystalline Quartz (SiO2)
Hardness: 7 Mohs; Color: Tan, grey, or translucent white; Luster: Waxy to dull; Crystal structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
- Hardness
- 7 Mohs
- Color
- Tan, grey, or translucent white
- Luster
- Waxy to dull
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Physical properties
Hardness: 7 Mohs; Color: Tan, grey, or translucent white; Luster: Waxy to dull; Crystal structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.65
Formation & geological history
Formed through the accumulation of silica-rich organic remains or chemical precipitation in sedimentary basins; primarily Paleozoic to Mesozoic era material. This specimen was anthropogenically modified through knapping.
Uses & applications
Historically used for hunting (projectile points/tools); currently sought for archeological study, historical collection, and as decorative artifacts.
Geological facts
Chert was preferred by prehistoric humans because it breaks into razor-sharp edges thanks to its conchoidal fracture. This specific point appears to be a bifacial lithic tool, likely a projectile tip or small scraper.
Field identification & locations
Identify in the field by looking for 'flake scars' (ripples from pressure flaking) and its distinct notched shape. Often found in tilled fields, near riverbeds, or sites of historical indigenous settlement.
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