Rock Identifier
Fossiliferous Limestone (Biogenic Sedimentary Rock (Calcium Carbonate with Fossils)) — sedimentary
sedimentary

Fossiliferous Limestone

Biogenic Sedimentary Rock (Calcium Carbonate with Fossils)

Hardness of 3 on the Mohs scale, typically white, gray, or tan with visible fossil impressions such as crinoids or brachiopods, dull to earthy luster, calcite crystal structure.

Identified More sedimentary
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Physical properties

Hardness of 3 on the Mohs scale, typically white, gray, or tan with visible fossil impressions such as crinoids or brachiopods, dull to earthy luster, calcite crystal structure.

Formation & geological history

Formed through the accumulation and compaction of organic carbonate debris, shell fragments, and skeletal remains in marine environments over millions of years.

Uses & applications

Used in construction, cement production, crushed stone, and as decorative landscape or architectural stone; prized by fossil collectors.

Geological facts

Many famous historical buildings and monuments, including parts of the Great Pyramids of Giza, are constructed from fossiliferous limestone.

Field identification & locations

Can be identified by testing with dilute hydrochloric acid (it will fizz due to the presence of calcium carbonate) and by observing visible fossil structures embedded in the rock matrix.