The Odyssey Marine Exploration’s successes

However the days of the individual treasure hunters, the Indiana Joneses of the sea, may be numbered, as specialist, well-resourced search and recovery companies send their vessels, bristling with technology, out into ever deeper waters.

Odyssey Marine Exploration Is one of a very small number of specialist companies with the budgets and expertise to use the new game-changing technologies to the full. At their disposal are advanced tethered robots that can dive to 4,000 meters and beyond, and lights and claws capable of withstanding the devastating, crushing pressures of the deep.

One important advance is the plastic cable, Dyneema, said to be the world’s strongest fibre, replacing the conventional steel cable which might break under the strain of its weight. The whole undersea operation is controlled with intricate electronic precision. From miles away, technicians can pick up individual coins and ingots from rotten wooden chests, and squeeze them through a tangle of metal in a ship’s interior to the surface.

One of Odyssey’s early successes came in 2004, when the company discovered the SS Republic, a ship lost in 1865 off the US coast. It recovered more than 50,000 coins, worth more than £40m. In 2007 Odyssey raised 16 tons of treasure worth an estimated $500 million from the Spanish galleon Nuestra Señora de las Mercedes, which sank off Portugal’s Atlantic coast. However the Spanish government successfully argued in a U.S. federal court that the treasure still belonged to Spain.

One of its biggest successes came in 2012, when it located the British vessel Gairsoppa, torpedoed 300 miles SW of Ireland by a German U-boat in 1941. It sank, with the loss of all but one of its 86-man crew and lies 2.9 miles down.

In 2012, contracted by the British government, the company sent out its search vessel Odyssey Explorer, which used a tethered robot, taking three and a half hours to reach the seabed, to recover 1,203 silver bars. The UK took the silver back, but Odyssey was well rewarded. To date, this is the heaviest and deepest cargo of precious metal yet lifted from a shipwreck. And there’s more to come, with yet more silver believed to be aboard the Gairsoppa.