sedimentary

Fossil Coral (Pleurodictyum)

Pleurodictyum sp. (Order Tabulata)

AI-generated identification · may be incorrect

Hardness: 3-4 (Calcite/Silica); Color: Tan, brown, and grey; Luster: Dull to earthy; Structure: Honeycomb-like or geometric corallites separated by dark walls.

Hardness: 3-4 (Calcite/Silica)
Color: Tan, brown, and grey
Luster: Dull to earthy

Identified June 20, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (Calcite/Silica); Color: Tan, brown, and grey; Luster: Dull to earthy; Structure: Honeycomb-like or geometric corallites separated by dark walls.

Formation & geological history

Formed as a marine colony during the Devonian period (approx. 360-410 million years ago) in shallow subtropical seas that once covered the Ohio River Valley.

Uses & applications

Primarily used for geological study, paleontological collecting, and educational purposes. Some agatized specimens are used in lapidary art.

Geological facts

The location provided (near Louisville, KY) is world-famous for the Falls of the Ohio, one of the largest exposed Devonian fossil beds in the world. These corals lived in warm, shallow seas long before the age of dinosaurs.

Field identification & locations

Look for the distinctive 'honeycomb' or 'waffle' pattern of individual coral cells (corallites). Field identification is common in limestone outcrops and riverbeds in the Kentucky/Indiana region.