Eight-year-old schoolboy Charlie Naysmith stands to make as much as £40,000 after finding a large chunk of yellow rock, which is actually a solid piece of whale sick, at Hengistbury Head, near Bournemouth.
According to the Bournemouth Echo, Charlie picked up the yellow rock, which weighs about 600g, and took it home to find out more about it. With the help of his parents he then discovered that the rock was in fact ambergris, which is highly sought after because it's used to prolong the scent of perfume. A pound of the substance can sell for as much as £6,300, which is why it's also known as 'floating gold'.
Charlie's dad Alex told the newspaper: "He is into nature and is really interested in it. We have discovered it is quite rare and are waiting for some more information from marine biology experts."
The family have been told that it's unlikely that more ambergris will be found in the same area as it could have been floating in the sea for decades before being washed up on the beach.
Ambergris is a waxy substance from the intestines of the sperm whale. It initially has a foul smell but exposure to sun and salt water turn into into a smooth lump of rock which feels waxy and has a sweet smell.
The substance is rarely found on British beaches and is more likely to be washed up in America and Australia.
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