fossil

Crinoid Columnal Fossil

Crinoid ossicle in sedimentary matrix

Mohs hardness 3-4, earthy brown to grey color, dull luster, crystalline calcium carbonate structure, distinct circular or star-shaped central lumen.

Identified November 13, 2026More fossil →

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Physical properties

Mohs hardness 3-4, earthy brown to grey color, dull luster, crystalline calcium carbonate structure, distinct circular or star-shaped central lumen.

Formed through the fossilization of marine crinoid echinoderm skeletal plates in ancient Paleozoic and Mesozoic shallow seas.

Valuable for educational study, amateur fossil collecting, and occasionally crafted into unique decorative jewelry.

Crinoids are commonly known as sea lilies and their disk-like columnals are sometimes historically called 'St. Cuthbert's beads'.

Identify in the field by looking for distinctive circular button-like disks with a central hole embedded in limestone or shale.

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

Fossil

Invertebrate fossil / Trace fossil

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