sedimentary

Fossiliferous Limestone

Calcareous biomicrite / Bioclastic limestone

AI-generated identification · may be incorrect

Hardness: 3-4 (Mohs); Color: Tan, buff, cream, to yellowish; Luster: Dull/Earthy; Structure: Clastic or bio-clastic texture containing shells; Composition: Primary calcite (CaCO3).

Hardness: 3-4 (Mohs)
Color: Tan, buff, cream, to yellowish
Luster: Dull/Earthy

Identified April 12, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (Mohs); Color: Tan, buff, cream, to yellowish; Luster: Dull/Earthy; Structure: Clastic or bio-clastic texture containing shells; Composition: Primary calcite (CaCO3).

Formation & geological history

Formed in marine environments through the accumulation of shell, coral, and algal debris. These sediments are lithified over millions of years through compaction and cementation. Often associated with Cretaceous to Cenozoic periods.

Uses & applications

Used primarily in construction for aggregate, building stone, cement production, and as an ornamental stone. Significant for paleontological study.

Geological facts

This rock can act as a natural record of past marine life. Some types, like Coquina, are composed almost entirely of shells. It is a major reservoir for groundwater and hydrocarbons.

Field identification & locations

Identify in the field by checking for fossil inclusions (shells, crinoids, etc.) and testing with a drop of cold dilute hydrochloric acid; it will vigorously effervesce (fizz). Found worldwide in places that were once ancient seabeds.