sedimentary

Gastropod Fossil (Snail Stone or Steinkern)

Class Gastropoda (Calcium Carbonate - CaCO3 / Silica - SiO2 replacing original shell)

Hardness: 3-7 (depending on mineralization like calcite or quartz); Color: Off-white, tan, gray; Luster: Dull or earthy; Crystal Structure: Amorphous or microcrystalline replacement; Cleavage: None (conchoidal fracture if silica-rich).

Hardness: 3-7 (depending on mineralization like calcite or quartz)
Color: Off-white, tan, gray
Luster: Dull or earthy

Identified May 23, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the process of permineralization or as an internal cast (steinkern). When a snail died, sediment filled the shell; over millions of years, the sediment hardened while the original shell dissolved or mineralized. Typically dates from the Cambrian to Holocene periods.

Uses & applications

Primarily used for educational purposes, scientific research, and as decorative collectibles. Large, well-preserved specimens are popular in interior design.

Geological facts

Gastropods are one of the few groups of animals that have successfully adapted to land, freshwater, and marine environments. The spiral shape follows a logarithmic progression known as a 'golden spiral'.

Field identification & locations

Identify by looking for the distinct planispiral or conispiral coiled shape. They are commonly found in limestone or shale beds near ancient coastal regions. Collectors should look for defined 'whorls' and clear aperture openings.

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