Divers searching the wreck of an 17th-century Swedish warship on the bed of the Baltic say they have found de Brie.

Sifting through the ancient timbers of the Kronan, a ship that sank in 1676 off the Swedish coast, they found not diamonds as they had hoped... but a cheese.

Inside a watertight pot was a semi-firm 340-year-old "dairy product" smelling of yeast and Roquefort cheese, expedition leader Lars Einarsson told AFP on Thursday.

"Unlike the others, I find its smell is quite pleasant," he said. "It smells of life."

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The unusual find is being sent to the Swedish University of Agricultural Sciences for tests.

The Kronan (Crown) sank off the island of Oeland, southeastern Sweden on June 1, 1676 in a battle with a Danish-Dutch fleet.

Squabbling officers and too much sail caused the ship to capsize and then explode. Only about 40 of the 800 crew survived.

The wreck was found in 1980 by Anders Franzen, an amateur naval archaeologist who 24 years earlier discovered the warship Vasa, which sank in 1628 in Stockholm port on its maiden voyage.

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