fossil

Crinoid Stem Fragment

Crinoid (Class Crinoidea)

Hardness: 3 (Calcite-based), Color: Grey to tan, Luster: Dull/Earthy, Crystal Structure: Hexagonal symmetry in segments (columnals), Cleavage: Rhombohedral (within calcite segments)

Identified July 2, 2026More fossil →

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Physical properties

Hardness: 3 (Calcite-based), Color: Grey to tan, Luster: Dull/Earthy, Crystal Structure: Hexagonal symmetry in segments (columnals), Cleavage: Rhombohedral (within calcite segments)

Formation & geological history

Formed during the Paleozoic or Mesozoic eras in warm, shallow marine environments; these are the calcified remains of prehistoric sea lilies or feather stars.

Uses & applications

Educational study, fossil collecting, and occasionally used in craft jewelry.

Geological facts

Crinoids are animals, not plants, despite their 'sea lily' nickname. They are related to starfish and sea urchins. Their stems are composed of stacked discs called columnals.

Field identification & locations

Identify by looking for cylindrical or disc-shaped segments with a central hole or star pattern (lumen). Common in limestone and shale deposits worldwide.