fossil

Fossilized marine shell fragment

Likely a bivalve or gastropod shell preserved as calcite (CaCO₃)

AI-generated identification · may be incorrect

Hardness about 3 Mohs; gray to cream, with curved growth lines, dull to pearly luster, and layered shell structure. It appears partially mineralized and weathered rather than crystalline throughout.

Identified August 16, 2026More fossil →

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Physical properties

Hardness about 3 Mohs; gray to cream, with curved growth lines, dull to pearly luster, and layered shell structure. It appears partially mineralized and weathered rather than crystalline throughout.

Formation & geological history

Formed from a marine mollusk shell later buried in sediment and preserved through mineral replacement or infilling, commonly during the Cenozoic or Mesozoic. Exact age and species require locality and detailed examination.

Uses & applications

Primarily a teaching, collecting, and decorative specimen; complete or identifiable fossils may have modest museum or jewelry appeal.

Geological facts

The visible concentric ridges and curved layered architecture are characteristic of shell growth, not igneous or metamorphic banding.

Field identification & locations

Common in limestone, beach deposits, and marine sedimentary rocks worldwide; dilute hydrochloric acid will usually fizz on exposed calcite. The specimen is too fragmentary for confident species identification from the image alone.