sedimentary

Likely flint or chert fragment

Microcrystalline quartz (SiO₂), probably flint/chert

AI-generated identification · may be incorrect

Dark gray-brown, opaque, dull to slightly waxy luster, with a lighter tan weathered cortex. Quartz hardness is about 7 Mohs; it has no cleavage and commonly breaks with curved conchoidal fractures. The image is insufficient for reliable density or exact texture assessment.

Identified August 10, 2026More sedimentary →

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Physical properties

Formation & geological history

Flint/chert forms when silica replaces or accumulates within sedimentary rocks, often limestone or chalk, during diagenesis. The specimen’s age cannot be determined visually; flint is common in Mesozoic and Cenozoic sedimentary terrains. Around 47.6°N, 19.3°E, transported flint/chert in alluvial or gravel deposits is plausible.

Uses & applications

Historically used for sharp tools and fire-starting; today it is mainly a teaching or collecting specimen, with limited aggregate and decorative use.

Geological facts

The pointed shape and apparent conchoidal fracture are consistent with a knapped flint fragment, though it could also be naturally broken. A steel file or quartz crystal should not scratch it easily.

Field identification & locations

Look for very fine, uniform texture, waxy appearance, sharp curved fracture edges, and a contrasting chalky cortex. Identification remains moderate-confidence because the image lacks scale and close fracture detail; a scratch test, streak, and fresh-break examination would help.