Polished Fossil Coral, East Lothian, Scotland (REF:FCSCOT3)

Corals are marine animals with a sac-like body (polyp), mouth, tentacles, and skeleton. They typically live in compact colonies of many identical individual polyps.

Although corals first appeared in the Cambrian period, some 542 million years ago, fossils are extremely rare until the Ordovician period, 100 million years later, when rugose and tabulate corals became widespread.