A Welsh man could be in the money after finding what he believes to be a huge lump of rare ambergris - a substance vomited by whales.
Andrew Hughes found the lump, produced in the intestines of sperm whales, while looking for fishing bait at Porth Dafarch near Trearddur Bay, Anglesey.
Professor Michel Kaiser, of Bangor University's marine ecology department, said scientists believe the substance forms to coat irritating objects in the whales' intestines.
He said the lump found by Mr Hughes could be worth "tens of thousands of US dollars" as it is used in the perfume industry.
Speaking to the BBC, Prof Kaiser said the lump "certainly seems to fit the description of what most people would describe as ambergris".
He added: "My understand of ambergris is that it's used in the perfume industry to enhance the scent or prolong the duration with which the scent lasts.
"Of course, it is illegal to actually trade in the substance in countries such as the United States, but when ambergris is found washed up on the coast it's rather like treasure trove.
Ambergris is a solid, waxy, flammable substance of a dull grey or blackish colour produced in the digestive system of sperm whales.
It is highly valued by perfumers as a fixative (allowing the scent to last much longer), but has now largely been replaced by synthetics.
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