fossil

Fossiliferous Limestone

Biogenic Sedimentary Rock containing invertebrate fossils

Hardness of 3 on the Mohs scale, earthy gray or tan color, dull to sub-vitreous luster, and reacts with hydrochloric acid.

Identified October 22, 2026More fossil →

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Physical properties

Hardness of 3 on the Mohs scale, earthy gray or tan color, dull to sub-vitreous luster, and reacts with hydrochloric acid.

Formed in marine environments through the accumulation and compaction of shell, coral, and skeletal debris over millions of years.

Used in construction, cement production, agriculture, and as collector specimens for fossil enthusiasts.

Fossiliferous limestone often preserves ancient marine ecosystems, capturing snapshots of prehistoric shallow seas.

Identify by visible fossil fragments embedded within a reactive carbonate matrix, commonly found in sedimentary rock layers worldwide.

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

Likely fossil oyster shell

Fossilized bivalve shell; exact species cannot be identified from the image

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

Fossiliferous limestone (likely a crinoidal or shell-fragment limestone)

Bioclastic limestone, composed chiefly of calcite (CaCO₃)

Porous limestone pebble

Calcite-rich limestone (primarily CaCO₃); exact identification is uncertain from the image

Weathered fossil bone fragment (identification uncertain)

Fossilized bone; exact taxon and mineral composition cannot be determined from the image