sedimentary
Chert Arrowhead (Projectile Point)
Microcrystalline Quartz (Chert/Flint)
Hardness: 7 on Mohs scale; Color: Brown, tan, and dark gray; Luster: Waxy to dull; Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
- Hardness
- 7 on Mohs scale
- Color
- Brown, tan, and dark gray
- Luster
- Waxy to dull
Identified More sedimentary →
Explore Chert Arrowhead (Projectile Point) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale; Color: Brown, tan, and dark gray; Luster: Waxy to dull; Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
Formation & geological history
Formed through the accumulation of silica-rich organic remains or chemical precipitation in sedimentary environments. As an artifact, it was created through flintknapping (pressure and percussion flaking) by prehistoric humans.
Uses & applications
Originally used as a hunting tool or weapon. Currently valued as an archaeological artifact and for private collections.
Geological facts
This specimen shows clear evidence of human modification, including a notched base and retouching along the edges. Chert is chosen for tools because its conchoidal fracture creates razor-sharp edges.
Field identification & locations
Can be identified by the visible flake scars and intentional symmetry. Often found in riverbeds, tilled fields, or archaeological sites where early populations settled. Artifacts should be documented and handled according to local salvage laws.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Mudstone
Argillite / Siliciclastic sedimentary rock
sedimentary
Brown Sandstone (River Rock)
Arenite
sedimentary
Cone-in-cone structure (Limestone)
Cone-in-cone structure (Secondary Sedimentary Structure)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary