sedimentary

Flint or chert flake/tool

Microcrystalline quartz (chalcedony), SiO₂

AI-generated identification · may be incorrect

Typically gray-brown with dull to waxy luster, conchoidal fracture, and no visible crystals; Mohs hardness 6.5–7, specific gravity about 2.6. The sharp, deliberately shaped edges and flake scars suggest a worked lithic artifact rather than an unmodified stone.

Identified September 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Chert forms when silica replaces or accumulates in sedimentary rocks, often during the Paleozoic–Cenozoic eras; this piece appears later retouched or knapped by humans. Exact age cannot be established from the image and requires archaeological context and expert examination.

Uses & applications

Historically used for cutting tools, arrowheads, scrapers, and fire-starting because fractures produce exceptionally sharp edges; modern chert is used as aggregate and decorative stone.

Geological facts

Field identification includes waxy texture, very hard surfaces, conchoidal fractures, and edges that can scratch glass. Common sources include limestone regions worldwide, especially England, France, Texas, Kansas, and the Great Lakes area.

Field identification & locations

Its apparent flaking may indicate a prehistoric artifact, but natural breakage can look similar; do not clean or alter it, and consult a local archaeologist or museum for provenance. A scale, edge-wear inspection, and microscopic analysis would improve identification.