Treasure hunter Ruben Collado speaks at the "Shipwrecked and Treasures" museum, in front of a model of the British 64-cannon ship Lord Clive, sunk in 1763 by the Spanish batteries, in Colonia del Sacramento, 188 km west of Montevideo. [Daniel Caselli/AFP]

More than 250 years after Spanish forces sank the British warship Lord Clive off the coast of Uruguay, treasure hunter Ruben Collado is working to raise it from its watery grave.

Collado believes the ship may have been carrying 100,000 gold coins when Spanish cannon fire sank it in 1763, as Britain and Portugal tried to seize the city of Colonia del Sacramento during the Seven Years' War.

The Argentine adventurer spent 14 years searching for the wreckage before finding it by accident in 2004, when the propeller of his boat struck a sunken mast as he trolled around the River Plate estuary.

After waiting more than 10 long years for authorization from the Uruguayan authorities, Collado is finally set to fulfill his dream: To haul what is left of the wreckage to the surface, repair its cracks and bring it to shore.

The 78-year-old bursts with energy as he discusses his plans, brushing aside conservationists' calls to leave the ship where it is and skeptics' doubts about its cargo.

"I'm a professional treasure hunter. If the ship doesn't have any treasure, investors don't put up any money," he says, his eyes alight as he looks out over the water from a bar in Colonia del Sacramento.