fossil

Likely fossil shell fragment

Indeterminate mollusk fossil; possibly a gastropod or bivalve in limestone

AI-generated identification · may be incorrect

Pale gray-white, irregular angular fragment with a dark brown curved internal feature and dull to slightly waxy luster; hardness likely about 3–4 if calcitic shell/limestone, with indistinct cleavage and specific gravity around 2.6–2.8.

Identified August 15, 2026More fossil →

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Physical properties

Formation & geological history

Likely mineralized or partially replaced calcium-carbonate shell preserved in sedimentary limestone; age cannot be determined from the photograph and may range from Paleozoic to Cenozoic.

Uses & applications

Primarily a teaching or collecting specimen; fossil limestone may be used as aggregate or ornamental stone, but this small fragment has no commercial use.

Geological facts

The dark curved marking may represent a shell whorl, hinge, or fossilized organic structure rather than a mineral crystal.

Field identification & locations

Look for repeated biological symmetry, growth lines, chambers, or shell curvature, and test cautiously with dilute hydrochloric acid or vinegar for calcite fizz. Common in marine sedimentary rocks worldwide, especially limestone and shale exposures.