fossil

Sand Dollar (Fossilized or Calcium Carbonate Skeleton)

Clypeasteroida (Order)

AI-generated identification · may be incorrect

Hardness: 2.5 - 3.5; Color: Off-white to tan; Luster: Dull or earthy; Structure: Fivefold radial symmetry (pentamerism); Composition: Calcium carbonate (calcite)

Hardness: 2
Color: Off-white to tan
Luster: Dull or earthy

Identified July 19, 2026More fossil →

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Physical properties

Hardness: 2.5 - 3.5; Color: Off-white to tan; Luster: Dull or earthy; Structure: Fivefold radial symmetry (pentamerism); Composition: Calcium carbonate (calcite)

Formation & geological history

Formed from the mineralized skeletal remains of sea urchins that live in shallow marine environments. While many found on beaches are recent, they frequently fossilize in sedimentary limestone and sandstone layers dating back to the Jurassic period.

Uses & applications

Primarily used for decorative purposes, jewelry, and educational collection. In fossilized form, they are valuable to paleontology.

Geological facts

The 'petals' on the surface are actually pores for respiratory feet. According to folklore, they represent the five wounds of Christ or coins lost by mermaids.

Field identification & locations

Identify by the circular flat disc shape and distinctive five-pointed star pattern. Commonly found on sandy coastlines or in ancient shallow marine sedimentary deposits.