fossil

Fossil Shell

Bivalvia (calcium carbonate)

Hardness of 3 on the Mohs scale, typically white or beige, vitreous to pearly luster, orthorhombic or trigonal crystal system.

Identified October 27, 2026More fossil →

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Physical properties

Hardness of 3 on the Mohs scale, typically white or beige, vitreous to pearly luster, orthorhombic or trigonal crystal system.

Formed through the fossilization of marine mollusk shells in sedimentary marine environments over millions of years.

Used in educational displays, fossil collecting, and occasionally as decorative items or jewelry.

Fossil shells provide crucial data for understanding ancient marine ecosystems and past global climates.

Identified by distinct growth rings and calcified shell structure; commonly found in sedimentary rock formations 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