fossil

Crinoid Stem Fossil

Crinoidea

AI-generated identification · may be incorrect

Cylindrical shape, often showing segmented structure or a central canal. Gray to dark gray color. Hardness depends on the replacing mineral, usually calcite or silica (Mohs 3-7). Luster is dull to sub-vitreous. Often found as small, loose, bead-like segments.

Identified August 31, 2026More fossil →

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Physical properties

Formation & geological history

Marine sedimentary environments from the Paleozoic era (Ordovician to Permian periods, roughly 485 to 252 million years ago). Formed by the fossilization of the stems of crinoids (sea lilies), a type of echinoderm. The skeletal remains, composed of calcium carbonate, were buried in sediment and often replaced by other minerals over time.

Uses & applications

Primarily collected by fossil enthusiasts. Sometimes used in simple jewelry or educational displays. In the past, individual segments were known as 'St. Cuthbert's beads'.

Geological facts

Crinoids are marine animals, not plants, despite their common name 'sea lilies'. They are related to starfish and sea urchins. While mostly extinct, some species still exist in deep oceans today.

Field identification & locations

Identified by their characteristic cylindrical, segmented shape with a central hole or star pattern (though not always visible). Common in many limestone deposits. Often found weathered out of matrix. Look for the distinct radial symmetry or central canal on the ends.