sedimentary

Fossiliferous limestone

Calcitic limestone, primarily calcium carbonate (CaCO₃), with visible shell or coral fossils

AI-generated identification · may be incorrect

Usually pale gray to cream, dull to slightly crystalline, with abundant embedded fossil fragments and irregular weathering; Mohs hardness 3, calcite cleavage, specific gravity about 2.7. Effervesces vigorously with dilute hydrochloric acid or strong vinegar.

Identified September 6, 2026More sedimentary →

Explore Fossiliferous limestone in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

A marine sedimentary rock formed when shells, corals, and other carbonate debris accumulated, compacted, and cemented on an ancient seafloor; commonly Paleozoic to Cenozoic in age, though exact age requires locality and fossil identification.

Uses & applications

Used as crushed aggregate, cement and lime feedstock, building stone, and educational or fossil-collecting specimens; attractive fossil-rich pieces may be cut and polished.

Geological facts

The large impressions and layered fragments likely represent mollusks, brachiopods, or colonial marine organisms, but the photograph is insufficient for a precise fossil identification.

Field identification & locations

Identify by visible fossils, pale color, relatively low hardness, and acid reaction; common in marine sedimentary basins worldwide. Avoid acid testing on valuable specimens and inspect broken surfaces for clearer fossil details.