A team of British scientists exploring an underwater mountain range have found a deposit of minerals 500 km (300 miles) from the coasts of the Canary Islands that might be a game-changer for the renewable energy sector.

The BBC reported that the team’s exploration of the Tropic Seamount range found the crust has of "astonishingly rich" rock. Samples brought back to the surface contain the scarce substance tellurium in concentrations 50,000 times higher than in deposits on land.

Tellurium is used in a type of advanced solar panel. The rocks are also rich in rare earth elements.

The Tropic Seamount mountain stands about 3,000 m (9,800 ft) tall –with a large plateau at its top, lying about 1,000 m (3,280 ft) below the ocean surface.

The researchers from the UK's National Oceanography Centre used robotic submarines and found that the crust is dark and fine-grained and stretches in a layer roughly 4cm thick over the entire surface of the mountain.

Dr. Bram Murton, the leader of the expedition, told the BBC that he had been expecting to find abundant minerals on the seamount but not in such concentrations.

“These crusts are astonishingly rich and that’s what makes these rocks so incredibly special and valuable from a resource perspective.”
He has calculated that the 2,670 t (2,943 st) of tellurium on this single seamount represents one-twelfth of the world's total supply.
The find could advance the deep-sea mining debate.

Currently there are a number of companies, including Nautilus Minerals, preparing to mine the sea floor and Papua New Guinea was the first country to issue a permit, to Solwara 1. However, there has been much resistance to opening the seafloors to mining.

One major concern is the effect of plumes of dust, stirred up by excavation of the ocean floor, spreading for long distances and smothering all life wherever it settles.

The BBC reported that to understand the implications, the expedition to Tropic Seamount conducted an experiment, the first of its kind, to mimic the effects of mining and to measure the resulting plume.

Deploying from the UK research ship James Cook, a remotely operated vehicle deliberately pumped out hundreds of litres of sediment-filled water every minute while other robotic sensors were positioned downstream in the ocean current.

According to Murton, early results indicate that dust was hard to detect 1km away from the source of the plume, suggesting that the impact of mining could be more localized than many fear.

But this comes as different disciplines within marine science are coming up with a range of perspectives on this emerging development.