AN UNDERSEA exploration vehicle is playing a key role in the salvage of what could be the most valuable shipwreck in history.

Soil Machine Dynamics, based in Newcastle, specialises in remote-controlled underwater vehicles.

It developed a craft called Zeus, which is being used by US company Odyssey Marine to recover the gold on board the SS Republic, which lies off the Georgia coast.

The ship sank during a voyage to New Orleans in 1865 carrying 20,000 gold coins. The Liberty Heads were the preferred currency of the time and each weighed 1oz.

Worth $400,000 when SS Republic set sail, the cargo is now valued at £100m. The money was to be used in the South's reconstruction, and to help relieve the post-civil war misery.

Mike Jones, sales and marketing manager at Soil Machine Dynamics, said: "Most of the machines we create are used for laying and burying cables and pipelines deep undersea.

"It is really exciting to see one of them being used to find such a historically important and valuable wreck."

Recovering treasure from SS Republic could be the first of many such tasks for Zeus, as other glamorous missions may lie ahead. Mr Jones said: "We should be hearing a lot more about Zeus in the coming months as Odyssey Marine has a deal with the British Government to recover nine tons of gold from the shipwreck of HMS Sussex."

Privately owned Soil Machine Dynamics is one of the world's leading underwater technology companies. It was founded more than 30 years ago by Dr Alan Reece, of the University of Newcastle, and employs about 70 people.

The firm has won two Queen's Awards and the UK's top engineering accolade - The MacRobert Award from the Royal Academy of Engineering.

Soil Machine Dynamics operates in the telecom, oil and gas, renewable energy, military and subsea mining markets.

Zeus, which was named by Odyssey Marine especially for this mission, weighs seven tons, has a 240hp propulsion system and can operate at depths of more than 8,000ft. The system's cameras feed high-resolution video signals to the operators at the surface, which enables them to control two manipulators for retrieving delicate artefacts.