sedimentary

Weathered fossiliferous limestone

Calcite-rich limestone (CaCO₃), possibly bioclastic or micritic limestone

AI-generated identification · may be incorrect

Gray-beige, dull to weakly sugary luster, fine-grained matrix with apparent fossil or shell fragments; calcite hardness Mohs 3, typically massive, with no prominent cleavage in hand-sized pieces. Effervesces strongly with dilute hydrochloric acid or vinegar, especially on a freshly scratched surface.

Identified September 8, 2026More sedimentary →

Explore Weathered 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

Sediment accumulated in a shallow marine environment and lithified by compaction and cementation; the visible texture may represent fossil debris. Exact geological age cannot be determined from the photograph.

Uses & applications

Used widely as crushed aggregate, cement and lime feedstock, building stone, and soil neutralizer; attractive fossiliferous pieces are collected but are rarely gem-quality.

Geological facts

Limestone is composed mainly of calcite and can preserve shells, corals, or microfossils. Weathering commonly roughens the surface and accentuates fossil grains or cavities.

Field identification & locations

Common in sedimentary terrains worldwide, including marine-platform regions. Confirm identification by its acid reaction, relatively low hardness, and inability to scratch glass; a close-up or polished surface is needed for fossil identification.