sedimentary

Fossiliferous limestone

Bioclastic calcarenite/calcirudite, chiefly calcite (CaCO₃)

AI-generated identification · may be incorrect

Pale cream, porous, and dull to faintly sugary; Mohs hardness 3, usually massive with no cleavage visible. Rounded fossil or shell fragments and small cavities are characteristic; dilute acid typically effervesces strongly.

Identified August 27, 2026More sedimentary →

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Physical properties

Formation & geological history

A sedimentary rock formed from accumulated, compacted, and cemented marine shell and skeletal debris, commonly during the Cenozoic or Mesozoic. Exact age cannot be determined from the photograph alone.

Uses & applications

Used as aggregate, cement and lime feedstock, dimension stone, and decorative material; fossil-rich pieces are mainly collected as specimens. This small example has modest commercial value.

Geological facts

The visible circular and irregular structures are likely fossil fragments or molds preserved in carbonate sediment. Limestone can dissolve in weak acid, producing a diagnostic fizz.

Field identification & locations

Common in former shallow tropical seas and exposed limestone terrains worldwide, including Florida, the Bahamas, the Caribbean, Europe, and parts of Asia. Identify it by its light color, fossil textures, softness, and acid reaction; avoid destructive testing on valuable specimens.