Rock Identifier
Fossilized Crinoid Stem in Matrix (Crinoid (Class: Crinoidea)) — fossil
fossil

Fossilized Crinoid Stem in Matrix

Crinoid (Class: Crinoidea)

Hardness 3 (calcite matrix) to 7 (if silicified/quartz presence); Color: white, tan, and grey; Luster: earthy to vitreous; Structure: segmented cylindrical columnals with stacked disk-like shapes.

Color
white, tan, and grey
Luster
earthy to vitreous
Identified More fossil
Explore Fossilized Crinoid Stem in Matrix in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Hardness 3 (calcite matrix) to 7 (if silicified/quartz presence); Color: white, tan, and grey; Luster: earthy to vitreous; Structure: segmented cylindrical columnals with stacked disk-like shapes.

Formation & geological history

Formed in marine environments as the remains of sea lilies (echinoderms) that settled in seafloor sediment. These specimens typically range from the Ordovician to the Permian periods (approx. 300-500 million years old).

Uses & applications

Educational specimens, fossil collecting, decorative lapidary work (such as Crinoidal Marble), and geological research.

Geological facts

Crinoids are known as 'sea lilies' because of their floral appearance, but they are actually animals related to starfish and sea urchins. In the UK, individual stem segments are sometimes called 'St. Cuthbert's beads'.

Field identification & locations

Look for stacked, circular 'cheerio' like patterns or segmented columns within limestone or shale. They are ubiquitous in Paleozoic limestone outcrops globally, especially in the Midwestern United States.