Rock Identifier
Flint (chert) hand axe (Cryptocrystalline silica (SiO₂), worked into a bifacial stone tool) — sedimentary
sedimentary

Flint (chert) hand axe

Cryptocrystalline silica (SiO₂), worked into a bifacial stone tool

AI-generated identification · may be incorrect

The dark gray, opaque specimen has sharp conchoidal edges and a matte-to-waxy luster; flint is about 7 on the Mohs scale and has no visible crystals or cleavage. The image appears to show a chipped, shaped artifact rather than an unworked rock.

Identified More sedimentary
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Physical properties

The dark gray, opaque specimen has sharp conchoidal edges and a matte-to-waxy luster; flint is about 7 on the Mohs scale and has no visible crystals or cleavage. The image appears to show a chipped, shaped artifact rather than an unworked rock.

Formation & geological history

Flint forms as silica-rich nodules in sedimentary rocks, commonly limestone or chalk. The tool’s age cannot be determined from the image; prehistoric examples were made by repeatedly striking flint to shape cutting edges.

Uses & applications

Flint was widely used for prehistoric cutting, scraping, and hunting tools; today it is mainly of archaeological and collector interest.

Geological facts

Flint’s conchoidal fracture produces exceptionally sharp edges. Stone tools are often dated and interpreted by their archaeological context, not appearance alone.

Field identification & locations

Look for a hard, fine-grained surface, curved impact scars, and deliberate flake-removal patterns. Flint occurs widely in sedimentary deposits, especially in Europe and parts of North America; provenance is essential for assessing an artifact.