fossil

Crinoid Stem Fossil

Crinoid columnal (Echinodermata)

Hardness: 3 on the Mohs scale (for calcite); Color: varies from grey and brown to white; Luster: vitreous to dull; Crystal structure: trigonal (calcite matrix); Cleavage: perfect rhombohedral in individual crystal units; Specific gravity: 2.7

Hardness: 3 on the Mohs scale (for calcite)
Color: varies from grey and brown to white
Luster: vitreous to dull

Identified August 4, 2026More fossil →

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Physical properties

Formation & geological history

Formed through the fossilization of marine organisms (crinoids, commonly known as sea lilies) that lived primarily during the Paleozoic era, particularly the Carboniferous period, accumulating in marine sedimentary environments.

Uses & applications

Used primarily in fossil collecting, educational displays, lapidary work (sometimes polished as 'star stones' or 'Indian beads'), and occasionally jewelry.

Geological facts

Crinoids are marine animals related to starfish and sea urchins. Their stems are composed of stacked disk-like segments called columnals that easily break apart after death, making individual segments very common fossils.

Field identification & locations

Easily identified in the field by their cylindrical shape, central hole (lumen), and distinctive star-like or circular patterning on the articular surfaces. Found worldwide in ancient limestone and shale deposits.

Other fossil specimens

See all

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

fossil

Sedimentary Outcrop (Sandstone/Shale)

Sedimentary bedrock formation (variable composition)

sedimentary

Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

sedimentary

Crinoid Stem Fossils (Indian Beads / St. Cuthbert's Beads)

Crinoid columnal ossicles (phylum Echinodermata)

fossil

Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

fossil

Fossiliferous Limestone

Limestone with embedded fossil cross-section

sedimentary