A British merchant ship sunk by the Nazis has given up a haul of 61 tons of silver, worth about $36 million, according to Odyssey Marine Exploration, a U.S.-based underwater archaeology and salvage company The treasure, consisting of 1,574 silver ingots and weighing a total of about 1.8 million ounces, was retrieved from the SS Gairsoppa, a 412-foot steel-hulled British cargo ship that sank on Feb. 17, 1941, after being torpedoed by a Nazi U-boat.
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The intact wreck was found in 2011 about 300 miles off the coast of Ireland, laying deeper than the Titanic at a depth of nearly 3 miles.
"We have accomplished a world-record recovery at a depth never achieved before," Mark Gordon, Odyssey's president and chief operating officer, said.
Indeed, an underwater robot used in the preliminary salvage operations took three and a half hours to descend to the bottom of the Atlantic Ocean.
The robot-captured video footage showed a unique view into the rusty ship, revealing a ladder leading to the forecastle deck, a stern compass and even an intact toilet.
The torpedo hole in the hull, which featured the red-and-black colors used by the British Indian Steam Navigation Company, was also clearly visible.
Bearing all the recovery costs, Odyssey has so far retrieved 2,792 silver ingots or more than 99 percent of the insured silver reported to be aboard the ship. The silver was worth about $630,000 when the Gairsoppa went down and is valued around $36 million at current prices.
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The precious metal, which adds to 1,218 ingots of high quality silver retrieved last year, has been transported to a secure facility in the United Kingdom.
The catch sets a new record for the deepest and largest precious metal salvage from a shipwreck.
"This was an extremely complex recovery," said Greg Stemm, Odyssey's chief executive officer. "The remaining insured silver was stored in a small compartment that was very difficult to access," he added.
En route from India to Liverpool, England, the Gairsoppa was in service of the Ministry of War Transport. She was laden with tea, iron and tons of silver.
Because of bad weather and insufficient coal, the merchant steamship was forced to break away from the military convoy off the coast of Ireland.
As the captain re-routed in emergency for Galway, on the west coast of Ireland, the Gairsoppa and its crew of 86 men were hit by a torpedo from a Nazi U-boat. She sank in icy seas within 20 minutes.
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The crew boarded three lifeboats. While two boats soon disappeared, a third lifeboat managed to sail for 13 days. Only one person, second officer Richard Ayres, survived the long journey to shore.
"Sources, including Lloyd's record of War Losses, indicate additional uninsured government-owned silver may have been aboard the SS Gairsoppa when she sank, but to date no uninsured silver has been located," Odyssey said in a statement.
Under the terms of a deal struck in 2011 with the UK Department for Transport, the Tampa, Fla.-based company will take 80 percent of the net proceeds.
Notable silver finds, including the first ingot recovered from the Gairsoppa, are currently on display at Odyssey's SHIPWRECK! exhibit at Discovery Times Square in New York City.
Image: Silver ingots recovered from the Gairsoppa shipwreck are valued at $36 million. Credit: Odyssey Marine Exploration, Inc., www.odysseymarine.com