fossil

Fossilized coral or stromatoporoid fragment

Likely tabulate coral (order Tabulata) or stromatoporoid; exact identification requires microscopy

AI-generated identification · may be incorrect

Cream-to-brown silicified or calcitic material with distinctive concentric, wavy growth bands and a dull to slightly waxy luster; hardness approximately 3–7 depending on calcite versus silica, with no obvious cleavage. The texture is organic and laminated rather than crystalline.

Identified August 29, 2026More fossil →

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Physical properties

Formation & geological history

A colonial marine organism formed successive skeletal layers on an ancient seafloor, later buried and mineralized. Similar fossils commonly range from Ordovician to Devonian age (about 485–359 million years old), though age cannot be determined from the image.

Uses & applications

Primarily a collecting, educational, or decorative specimen; polished fossil coral is sometimes used in jewelry and cabochons. It has little industrial value as an isolated fragment.

Geological facts

The swirling bands record repeated biological growth and resemble tree rings, but they formed underwater. Fossil corals are important indicators of ancient shallow, warm marine environments.

Field identification & locations

Look for repeated corallite pores, honeycomb texture, or layered internal walls on a freshly broken or magnified surface; a hand lens is useful. Common in Paleozoic limestone deposits worldwide, including North America, Europe, and Australia.