fossil

Shark Tooth Fossil

Chondrichthyes tooth

Mohs hardness 5-5.5; brown to dark gray; vitreous to dull luster; composed mainly of fluorapatite and calcium phosphate.

Identified October 17, 2026More fossil →

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Physical properties

Mohs hardness 5-5.5; brown to dark gray; vitreous to dull luster; composed mainly of fluorapatite and calcium phosphate.

Formed through the process of permineralization where original organic material is replaced by minerals over millions of years.

Prized by fossil collectors, used in educational displays, and crafted into jewelry.

Sharks lose thousands of teeth in a lifetime, making their teeth among the most common vertebrate fossils found worldwide.

Found in marine sedimentary rock layers and riverbeds; identified by characteristic triangular shape and serrated edges.

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

Fossil oyster shell

Oyster (family Ostreidae); shell composed chiefly of calcite (CaCO₃)