Rock Identifier
Fossilized Gastropod Steinkern (Gastropoda internal mold) — fossil
fossil

Fossilized Gastropod Steinkern

Gastropoda internal mold

AI-generated identification · may be incorrect

Hardness varies around 3-4 on Mohs scale depending on mineral replacement; color is typically beige or brown; dull luster; amorphous internal cast structure with distinct shell whorl impressions.

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Physical properties

Hardness varies around 3-4 on Mohs scale depending on mineral replacement; color is typically beige or brown; dull luster; amorphous internal cast structure with distinct shell whorl impressions.

Formation & geological history

Formed when a snail shell filled with sediment, hardened into rock, and the original shell dissolved away over millions of years in marine or freshwater environments.

Uses & applications

Collected by fossil enthusiasts, used in educational displays, and studied by paleontologists to understand ancient ecosystems.

Geological facts

This type of fossil is known as a steinkern, which is a German word meaning stone core. They often preserve the internal anatomy of ancient mollusks while losing the exterior shell detail.

Field identification & locations

Identify by looking for spiral whorl shapes and a heavy, stony weight in sedimentary limestone or sandstone beds. Common worldwide in Paleozoic through Cenozoic deposits.

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