London ( CNN ) -- A shipwreck laden with 200 tonnes of silver -- the largest haul of precious metal ever found at sea -- has been discovered in the North Atlantic . The wreck of the SS Gairsoppa , a British steamship sunk by a German U-Boat during World War II , was found 300 miles off the coast of Ireland by underwater archaeology and salvage experts Odyssey Marine Exploration . The U.S. company has explored the wreck which lies 4,700 meters down , on the sea bed , using a remotely operated submarine . It now hopes to bring the SS Gairsoppa 's valuable cargo of silver bullion to the surface . Odyssey 's senior project manager Andrew Craig said : `` We 've accomplished the first phase of this project - the location and identification of the target shipwreck . Now we 're hard at work planning for the recovery phase . '' Craig said he was `` extremely confident '' the company would be able to salvage the seven million ounces of silver ( 200 tonnes ) , which was worth more than Â£600,000 in 1941 . The 412ft steel-hulled SS Gairsoppa was built in 1919 for the British India Steam Navigation Company , and originally served as a cargo ship on routes to and from the Far East , East Africa and Australia . When the Second World War broke out , she was ordered into Britain 's merchant navy . In February 1941 , the SS Gairsoppa was traveling from Calcutta , India , to Liverpool , Britain , with a cargo of silver , tea and pig iron when she became separated from the rest of her convoy in bad weather . As the crew battled to bring the ship , which was running low on fuel , safely in to port at Galway in Ireland , she was struck by a torpedo from a German U-Boat . More than 30 of the 85 sailors on board the SS Gairsoppa are believed to have made it onto lifeboats , but only one , Second Officer Richard Ayres made it safely home , landing in Cornwall after drifting at sea for two weeks . Odyssey says it does not expect to find any human remains on the wreck . Neil Cunningham Dobson , Odyssey 's Principal Marine Archaeologist , said that -- as a former merchant mariner -- the story of the SS Gairsoppa had struck a chord with him . `` Even though records indicate that the lifeboats were launched before the ship sank , sadly most of her crew did not survive the long journey to shore , '' he said . `` By finding this shipwreck , and telling the story of its loss , we pay tribute to the brave merchant sailors who lost their lives . '' The company won a British government contract to search for and salvage the ship . Under the terms of the agreement , it will keep 80 % of the value of any silver recovered from the wreck .
SS Gairsoppa was sunk by a German U-Boat in February 1941 . The ship was carrying a cargo of silver bullion , tea and pig iron . Only one of the 85 people on board survived the sinking . Wreck found 300 miles off the coast of Ireland , at a depth of 4,700 meters .