An gigantic oyster fossil that was trawled up by fisherman has been MRI scanned to reveal what could be a pearl as large as a golf ball.
The mollusc was given to an aquarium where experts used growth rings to determine how old it was, and were keen to discover if there was a rare gem inside.
The medical charity Cobalt, which provides state of the art scanning services, heard of the prehistoric find and volunteered to scan the oyster.
The scan showed a mysterious smooth object about the size of a golf ball inside the 145-million-year-old shell.
If it were removed and identified as a pearl, it could be worth many thousands of pounds.
But experts have decided not to explore the contents any further because the oyster would have to be destroyed.