fossil

Fossiliferous Limestone

Fossiliferous Limestone (CaCO3 with organic inclusions)

AI-generated identification · may be incorrect

Hardness: 3-4 (Mohs scale); Color: buff, tan, or grey; Luster: dull to earthy; Texture: clastic/bioclastic with visible shell fragments and imprints.

Hardness: 3-4 (Mohs scale)
Color: buff, tan, or grey
Luster: dull to earthy

Identified July 15, 2026More fossil →

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Physical properties

Hardness: 3-4 (Mohs scale); Color: buff, tan, or grey; Luster: dull to earthy; Texture: clastic/bioclastic with visible shell fragments and imprints.

Formation & geological history

Formed in warm, shallow marine environments from the accumulation of calcium carbonate and the skeletal remains of marine organisms like brachiopods and mollusks over millions of years.

Uses & applications

Used primarily in construction as building stone, gravel, and in the production of cement. Larger slabs with clear fossils are used for decorative architecture or as educational specimens.

Geological facts

These rocks represent ancient seabeds; the fossils within can be used to date the geological layer and provide information about the paleoecology of the region during the time of deposition.

Field identification & locations

Identify by looking for visible shell impressions or skeletal fragments in a fine-grained matrix that fizzes when exposed to weak acid (diluted HCl). Commonly found in sedimentary basins worldwide.