fossil

Crinoid Stem Fossil

Class Crinoidea (Echinodermata)

AI-generated identification · may be incorrect

Hardness: 3 (calcite composition), Color: Grey to brownish-grey, Luster: Dull/earthy, Structure: Circular or star-shaped cross-sections resembling stacked discs or Cheerios.

Identified July 18, 2026More fossil →

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Physical properties

Hardness: 3 (calcite composition), Color: Grey to brownish-grey, Luster: Dull/earthy, Structure: Circular or star-shaped cross-sections resembling stacked discs or Cheerios.

Formation & geological history

Formed during the Paleozoic era (dating back 250 to 500 million years) from the skeletal remains of sea lilies in shallow marine environments. The soft tissue decayed, leaving behind calcified stem segments.

Uses & applications

Scientific study, educational specimens, jewelry (beads), and collector items.

Geological facts

Crinoids are actually animals, not plants, and are closely related to starfish and sea urchins. Their stems are often found fragmented into individual 'columnals' which are sometimes called 'Indian beads' or 'St. Cuthbert's beads'.

Field identification & locations

Look for stacked circular patterns or individual disc shapes in limestone or shale. They are extremely common in the Midwestern United States and the United Kingdom.