A man from Morecambe believes his dog has found a rare piece of whale vomit while walking on the beach.

Ken Wilman said when Madge the dog "started poking at a rather large stone" he realised it was unusual.

He left the ambergris on the beach but "something triggered in my mind" and, after doing some research, he went back to get it.

The substance, which is found in the digestive system of sperm whales, is said to be valuable and used in perfume.