sedimentary

Fossilized Echinoid (Sea Urchin)

Echinoidea (Fossil)

AI-generated identification · may be incorrect

Hardness: 3 (calcite); Color: white to light gray; Luster: dull to earthy; Structure: pentameral (five-fold) symmetry with visible pore pairs; Composition: Calcium Carbonate (CaCO3).

Hardness: 3 (calcite)
Color: white to light gray
Luster: dull to earthy

Identified June 22, 2026More sedimentary →

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Physical properties

Hardness: 3 (calcite); Color: white to light gray; Luster: dull to earthy; Structure: pentameral (five-fold) symmetry with visible pore pairs; Composition: Calcium Carbonate (CaCO3).

Formation & geological history

Formed through the process of permineralization or replacement where the original organic shell of a sea urchin is replaced by minerals like calcite or silica within marine sedimentary deposits, often dating from the Paleozoic to the Cenozoic era.

Uses & applications

Primarily for fossil collecting, educational scientific study, and occasionally used in decorative jewelry or as curios.

Geological facts

In folklore, these fossils were often called 'fairy loaves' or 'shepherds' crowns' and were believed to have magical properties like preventing bread from going moldy.

Field identification & locations

Identified by the distinct five-sided star pattern on the surface; commonly found in limestone or chalk quarries and coastal cliffs. Collectors should look for the characteristic round or heart shape with radiating patterns.