fossil

Fossil coral (likely a weathered colonial coral fragment)

Fossilized scleractinian coral; genus and age cannot be determined from the image

AI-generated identification · may be incorrect

Cream to ochre, porous surface with irregular cup-like openings that may be coral corallites; hardness and mineral composition cannot be confirmed visually. Fossil coral is commonly calcite or aragonite, Mohs 3–4, with a nonmetallic, dull luster.

Identified October 4, 2026More fossil →

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Physical properties

Formation & geological history

Coral skeletons accumulated in warm, shallow marine reefs and were later buried and mineralized, often during the Paleozoic or Mesozoic; this specimen’s age is unknown.

Uses & applications

Collected and displayed as a fossil; fossil coral is also sometimes cut and polished for decorative objects and jewelry.

Geological facts

The repeated pits may be corallites—the skeletal cups once occupied by individual coral polyps—but similar holes can also result from erosion or boring organisms.

Field identification & locations

Look for a consistent pattern of corallite walls and internal partitions across a broken or polished surface; the image alone does not establish that this is coral. Fossil corals occur in ancient marine limestone deposits worldwide.