sedimentary

Chert (Flint Arrowhead)

Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Brown, tan, translucent; Luster: Waxy to vitreous; Crystal structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 6
Color: Brown, tan, translucent
Luster: Waxy to vitreous

Identified July 5, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Brown, tan, translucent; Luster: Waxy to vitreous; Crystal structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed as nodules or beds in sedimentary rocks through the precipitation of silica from groundwater or the accumulation of siliceous organisms like diatoms and radiolaria. This specific specimen has been human-worked through percussion and pressure flaking.

Uses & applications

Historically used for stone tools and weapons (arrowheads, scrapers, knives) due to its sharp edges; used today in fire-starting kits and as a collector's item in archaeology and geology.

Geological facts

This specimen is an artifact, specifically a lithic projectile point fragment. Chert/Flint was one of the first materials traded over long distances by prehistoric humans because of its utility and predictability when knapped.

Field identification & locations

Identify in the field by its distinctive waxy texture and conchoidal fracture (curving, shell-like breaks). Often found in limestone or chalk beds. If flaked into a shape, it is an archaeological artifact and should be documented in situ.