sedimentary
Chert (Arrowhead Preform or Point)
Chert (Microcrystalline Quartz, SiO2)
Hardness: 7 (Mohs); Color: Brown/Ochre due to iron oxide; Luster: Waxy to dull; Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture).
- Hardness
- 7 (Mohs)
- Color
- Brown/Ochre due to iron oxide
- Luster
- Waxy to dull
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Physical properties
Hardness: 7 (Mohs); Color: Brown/Ochre due to iron oxide; Luster: Waxy to dull; Structure: Cryptocrystalline; Cleavage: None (conchoidal fracture).
Formation & geological history
Formed through the accumulation of silica-rich organic debris or chemical precipitation in marine environments; this piece shows human modification (knapping).
Uses & applications
Historically used for stone tools and weaponry; currently valued as an archaeological artifact or for lithic studies.
Geological facts
This specimen appears to be an anthropogenic artifact, possibly a projectile point or 'preform'. The scalloped edges indicate intentional 'knapping' or flaking by humans.
Field identification & locations
Look for conchoidal (shell-like) fracture scars and symmetrical shaping. Found in creek beds or fields where ancient human activity occurred. Handle with care for professional authentication.
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