sedimentary

Fossiliferous limestone

Bioclastic limestone, predominantly calcite (CaCO₃)

AI-generated identification · may be incorrect

Light gray to tan, rough and granular, with visible shell or coral fragments in a micritic/calcitic matrix; calcite is Mohs hardness 3, has vitreous to dull luster, rhombohedral cleavage, and reacts vigorously with dilute hydrochloric acid. Specific gravity is typically 2.6–2.8.

Identified September 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed when marine shells, skeletal debris, or reef material accumulated, compacted, and cemented on an ancient seafloor; age cannot be determined from the photograph and may range from Paleozoic to Cenozoic.

Uses & applications

Used as crushed aggregate, cement and lime feedstock, building stone, and decorative fossil material; attractive polished pieces may be used for display.

Geological facts

The rounded pale inclusions appear to be fossil shells or bioclasts, possibly brachiopods, bivalves, or coral fragments, but exact identification requires magnification and a fresh surface.

Field identification & locations

Identify by its fossil-rich texture and acid reaction; common in former shallow-marine sedimentary basins worldwide. Avoid destructive testing on valuable specimens and inspect fossils with a hand lens.