fossil

Fossilized coral fragment

Fossil coral, likely colonial coral; original skeleton composed chiefly of calcium carbonate (aragonite or calcite)

AI-generated identification · may be incorrect

Tan, oblong fragment with fine, repeated ridges and pores; hardness depends on preservation, typically about 3–4 Mohs if calcitic. The image does not show enough detail to determine coral type or crystal structure confidently.

Identified October 15, 2026More fossil →

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Physical properties

Formation & geological history

Coral skeletons accumulated in ancient marine reefs and were later buried and preserved as fossils, often with mineral replacement. Age cannot be determined from appearance alone.

Uses & applications

Primarily collected as a natural-history specimen; fossil coral is also cut and polished for decorative objects and jewelry.

Geological facts

The small pits and regular surface pattern are consistent with coral corallites or skeletal texture, but a shell or other fossil fragment is another possibility.

Field identification & locations

Look for repeated corallite cups, pores, or ridges rather than the continuous growth lines of a shell. Fossil corals occur in sedimentary rocks worldwide; this small specimen is likely worth about $1–$10.