sedimentary
Fossilized Echinoid (Sea Urchin)
Echinoidea (Fossil)
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 More 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.
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