fossil

Fossilized Nut / Coprolite / Concretion

Trace Fossil / Permineralized Plant Material

AI-generated identification · may be incorrect

Hardness varies between 3 and 5 on the Mohs scale depending on the mineral replacement (often calcite or silica). Color ranges from light brown to dark brown or grey. Luster is dull to earthy. Structure is organic-mimetic, retaining the shape of a seed or nut.

Identified August 2, 2026More fossil →

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Physical properties

Formation & geological history

Formed through permineralization or replacement where organic material is slowly substituted by minerals like silica or calcium carbonate in sedimentary environments over millions of years.

Uses & applications

Valued by fossil collectors, used for educational purposes and paleobotanical research.

Geological facts

Specimens like this can sometimes be mistaken for coprolites (fossilized feces) or ordinary ironstone concretions. Fossilized nuts and seeds provide crucial insights into ancient prehistoric ecosystems and flora.

Field identification & locations

Found weathering out of sedimentary rock layers, particularly in river gravels, beaches, and fossiliferous shale formations. Look for distinct botanical shapes and heavier-than-expected weight.