Good fortune has never smelled so bad. The Mirror reports Gary and Angela Williams found a lump of "floating gold"—more accurately described as whale vomit—Sunday while walking on a British beach.

It wasn't too hard to find the ambergris, which is both rare and valuable; they just followed their noses. "It's a very distinctive smell, like a cross between squid and farmyard manure," Gary says.

Ambergris is used in perfume-making to extend the lifespan of scents, and Smithsonian notes the not-so-delectable sounding item was once eaten: Casanova was said to view it as an aphrodisiac and incorporate it into his chocolate mousse.

Gary and Angela had previously read about ambergris, so they knew the 3.5-pound lump shouldn't be ignored. It could get them more than $70,000, according to the Guardian (though Atlas Obscura says the going rate is more like $10,000 per pound), which the couple would use to purchase a mobile home.

They're currently talking with potential buyers in France and New Zealand. Ambergris, which feels like a hard ball of sticky wax after hardening on a beach, is made in the intestines of whales, possibly to protect them from sharp objects they're unable to digest, like squid beaks.

(A British man who found a soccer ball-sized piece of whale vomit in 2013 sold it for $68,000.)

This article originally appeared on Newser: Lucky Couple Finds Precious Lump of Smelly Whale Vomit

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