sedimentary

Fossilized Gastropod Shell

Gastropoda (Class)

Hardness: 3-4 (Calcite/Aragonite replacement), Color: Cream, tan, or gray, Luster: Dull to pearly, Structure: Spiral whorls with a distinct aperture, Cleavage: None (conchoidal fracture if broken)

Identified June 22, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (Calcite/Aragonite replacement), Color: Cream, tan, or gray, Luster: Dull to pearly, Structure: Spiral whorls with a distinct aperture, Cleavage: None (conchoidal fracture if broken)

Formation & geological history

Formed through permineralization or replacement where a snail shell was buried in sediment (typically mud or sand) in a marine or freshwater environment. These can date from the Cambrian period to the Holocene.

Uses & applications

Commercial fossil trade, education, paleontology research, and sometimes used in jewelry or decorative crafts.

Geological facts

Gastropods are one of the few groups of organisms that have been successful in all three primary habitats: marine, freshwater, and terrestrial. Their fossils help geologists determine the age and environmental conditions of rock layers.

Field identification & locations

Identified by the coiled helical shape. Often found in limestone, shale, or sandstone outcrops. Collectors should look for weathered surfaces of sedimentary rock where the harder fossil may stand out.