fossil

Fossilized Crinoid Stem Cross-Section

Crinoidea

AI-generated identification · may be incorrect

Round or coin-like shape, often composed of calcite or replaced by silica. The color varies based on the surrounding matrix, often tan, brown, or grey. Hardness depends on replacement mineral (calcite is 3, quartz/silica is 7).

Identified August 25, 2026More fossil →

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Physical properties

Formation & geological history

Crinoids are marine animals that lived during the Paleozoic era, particularly abundant in the Mississippian period. This specimen is a segment of the stem (columnal). Formed in shallow marine environments.

Uses & applications

Commonly collected as fossils. Sometimes used in jewelry or as educational specimens. 'Indian beads'.

Geological facts

Crinoids are sometimes called 'sea lilies' because they look like plants, but they are actually echinoderms, related to starfish and sea urchins.

Field identification & locations

Identified by their characteristic circular shape with a central hole or star pattern (lumen). Commonly found in sedimentary rocks like limestone and shale. Look for them in areas with Paleozoic marine deposits.