fossil

Red Coral and Shell

Corallium rubrum and Conus/Mollusk shell

Hardness of 3-4 on Mohs scale, red and white colors, vitreous to dull luster, organic-mineral composition of calcium carbonate.

Identified November 6, 2026More fossil →

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Physical properties

Hardness of 3-4 on Mohs scale, red and white colors, vitreous to dull luster, organic-mineral composition of calcium carbonate.

Formed organically from marine invertebrate skeletal remains and mollusk nacre over centuries in shallow to deep marine environments.

Used primarily in traditional jewelry, decorative arts, and cultural ornamentation.

Precious coral has been harvested for jewelry since ancient times and was widely traded across ancient civilizations.

Identified by its organic origin, reaction to acid due to calcium carbonate, and distinctive natural growth patterns.

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