sedimentary
Crinoid Columnal Fossil
Crinoid ossicle (Class Crinoidea)
Hardness: 3 (calcite); Color: Tan, grey, or white; Luster: Dull to vitreous; Structure: Disk-shaped or ring-like with a central hole (lumen); Composition: Calcium carbonate.
- Hardness
- 3 (calcite)
- Color
- Tan, grey, or white
- Luster
- Dull to vitreous
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Physical properties
Hardness: 3 (calcite); Color: Tan, grey, or white; Luster: Dull to vitreous; Structure: Disk-shaped or ring-like with a central hole (lumen); Composition: Calcium carbonate.
Formation & geological history
Formed from the fossilized remains of marine animals related to starfish and sea urchins. These segmented stems lived during the Paleozoic era (approx. 250-500 million years ago) in shallow seas.
Uses & applications
Educational specimens, hobbyist collecting, and sometimes used in folk jewelry (known as 'St. Cuthbert's beads').
Geological facts
Crinoids are often called 'sea lilies' because they resemble plants, but they are actually animals. Their fossilized stem segments are among the most common fossils found in limestone layers worldwide.
Field identification & locations
Identify by the distinct wheel or donut shape with a central hole. Often found in limestone outcrops, creek beds, or gravel deposits where ancient seafloors are exposed.
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