‘Mysterious rock’ discovered by dog on Scottish beach is not what it seems - and it could be worth thousands

A “mysterious rock” a dog found on a Scottish beach could earn her owner thousands.

Patrick Williamson, 37, was stunned when his pup dropped her ball and sprinted over to retrieve the 5oz “rock”.

Fisherman Paul quickly realised it was ambergris - a valuable chunk of vomit produced in the intestines of sperm whales.

Whales are usually able to regurgitate problem foods but if they can’t they produce a waxy substance to protect their intestinal tract.

The whale will expel the valuable ambergris, which will float in the sea until it washes up on the shore – ready to be found by a lucky treasure hunter.

In the past, large lumps of the substance have sold for millions, motivating Paul to get his new discovery tested.