fossil

Fossiliferous limestone

Bioclastic limestone, chiefly calcite (CaCO₃), containing shell or coral fragments

AI-generated identification · may be incorrect

Light gray to cream, dull to slightly waxy, with abundant curved fossil molds/fragments and irregular granular texture. Calcite hardness is about Mohs 3, with weak cleavage; it should fizz in dilute hydrochloric acid or strong vinegar, though weathered surfaces may react weakly.

Identified September 13, 2026More fossil →

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Physical properties

Formation & geological history

A sedimentary rock formed when marine organisms accumulated on a seafloor and their carbonate remains were compacted and cemented. The exact geological age and fossil identity cannot be determined reliably from this photograph.

Uses & applications

Used as aggregate, cement and lime feedstock, building stone, and decorative material; attractive fossil-rich pieces are collected or used as displays.

Geological facts

The rounded forms may represent shells, corals, or other marine fossils preserved in carbonate sediment. Acid reaction and close inspection of exposed cross-sections are useful confirmation tests.

Field identification & locations

Common in former shallow tropical seas and limestone regions worldwide, including parts of North America, Europe, and Asia. Look for identifiable shells, consistent carbonate matrix, and acid effervescence; avoid damaging valuable specimens.