A study published by Japanese researcher Yutaro Takaya, from Tokyo’s Wasada University, states that an estimated 16 million tons of rare earth elements have been identified in sea sludge off Japan’s Minamitorishima Island. In the study, Takaya stated that his team hopes to develop ways of extracting the materials within five years.
Some rare earths, primarily neodymium and praseodymium, are used in the manufacture of high-performance permanent magnets, which as well as being a key enabler of hybrid and electric vehicles are used extensively in the automotive industry to produce electric components such as those found in seats, mirrors, wipers, steering and braking.
Currently, China controls 90% of the rare earths market, due to the high concentration of rare earth deposits within its borders. Of the 120 million tons of land-based rare earth deposits globally, 44 million are said to be located in China, 22 million in Brazil and 18 million in Russia. China extracted 150,000 tons of rare earths in 2016, but has in the past restricted the supply of rare earths outside its borders for strategic and political reasons.
In addition, prices of Chinese rare earths are currently rising due to the stricter enforcement of its mining laws and a global surge in the demand for hybrid and electric vehicles. As the second largest consumer of rare earths globally, Japan is one of many countries working to decrease its reliance on Chinese exports.
Regarding the potential to extract rare earths from the sea-bottom, Takaya told the Agence France-Presse (AFP), “We are not talking about some dream technology of the distant future. We are conducting studies to make this possible.” However, a number of experts consulted by AFP stated that as there is currently no profitable way of extracting rare earths from the sea-bottom, the find may not prove a viable solution.
Ryan Castilloux, Director of France’s Adamas Intelligence consultancy, stated, “It takes up to ten years or more to advance a rare earth project from discovery into a producing mine on land, so I do not expect it will be faster in the sea. The discovery in Japan is still in its very early stages and it will take several years to determine if mining will be feasible.”
Mark Hannington, from Germany’s Helmholtz Center for Ocean Research, added, “Although 16 million tons is a large number, there is no evidence that this amount could be recovered economically or sustainably.” In addition, a number of experts highlighted that the concentration of rare earths on Japan’s sea-bottom is relatively weak, at less than 1% – therefore, stated Castilloux, to produce 1,000 tons of rare earth would require the mining of more than one million tons of mud.
However, Japan’s Takaya stated that the find “should contribute to the ‘resource security’ of Japan’,” as well as having strategic importance in future negotiations. He explained, “Japan will be able to say, ‘if prices are made to go above this level, we can look into developing sea-bottom rare earths.’”