fossil

Fossil gastropod shells

Fossilized marine gastropods; likely internal or external casts of coiled mollusks (Gastropoda)

AI-generated identification · may be incorrect

Tan to brown, tightly spiral, granular specimens with preserved whorl patterns; commonly composed of calcite or silica replacing original shell. Typical hardness is about 3 (calcite) to 7 (silica), with dull to earthy luster and no visible crystal cleavage.

Identified September 7, 2026More fossil →

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Physical properties

Formation & geological history

Originally marine snail shells buried in carbonate-rich sediment, later mineralized or preserved as molds/casts during diagenesis. Their age cannot be determined from the image, but such fossils commonly range from Paleozoic to Cenozoic.

Uses & applications

Used mainly for education, museum displays, and fossil collecting; attractive polished examples may be decorative but have little industrial use.

Geological facts

The spiral geometry reflects gastropod growth, with each successive whorl expanding around the earlier ones. Surface texture can preserve details of the original shell or sediment infill.

Field identification & locations

Identify by the regular logarithmic spiral, expanding whorls, and fossilized stony texture; distinguish from modern shells by their weight, lack of nacre, and mineral-filled interior. Common in limestone and marine sedimentary formations worldwide.