sedimentary

Gastropod Fossil (Snail Internal Cast)

Class Gastropoda (Steinkern)

AI-generated identification · may be incorrect

Hardness: 3-4 (calcite-based); Color: Tan, beige, or light brown; Luster: Dull or earthy; Crystal structure: Amorphous or microcrystalline calcite; Cleavage: None; Specific gravity: Approx 2.6-2.8

Hardness: 3-4 (calcite-based)
Color: Tan, beige, or light brown
Luster: Dull or earthy

Identified May 23, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (calcite-based); Color: Tan, beige, or light brown; Luster: Dull or earthy; Crystal structure: Amorphous or microcrystalline calcite; Cleavage: None; Specific gravity: Approx 2.6-2.8

Formation & geological history

Formed through permineralization or as a 'steinkern' (internal cast) where sediment fills a shell that later dissolves. Usually Carboniferous to Cretaceous period, found in ancient marine or freshwater sedimentary layers.

Uses & applications

Primarily for geological study, educational teaching tools, and private fossil collections.

Geological facts

Gastropods are one of the few groups that successfully live in marine, freshwater, and terrestrial environments. Internal casts like this are often called 'Murchisonia' or 'Maclurites' depending on the specific genus and age.

Field identification & locations

Look for a coiled or spiral shape with visible whorls. Commonly found in limestone outcrops, road cuts, and riverbeds. Collectors should look for distinct sutures between the whorls.