Japanese researchers have discovered vast reserves of rare-earth elements in deep-sea mud, with the potential, they explain, to meet global demand on a “semi-infinite basis” for the elements needed to build high-tech products such as cellphones, electric vehicles, and even modern tanks, missiles and aircraft.
The deposit, a roughly 965-square-mile Pacific Ocean seabed near the remote Minamitori Island about 1,150 miles southeast of Tokyo, contains more than 16 million tons of rare-earth oxides. The study, conducted by Waseda University’s Yutaro Takaya and the University of Tokyo’s Yasuhiro Kato, along with members from businesses and government institutions, estimates the deposit holds 780 years’ worth of the global supply of yttrium, 620 years’ worth of europium, 420 years’ worth of terbium and 730 years’ worth of dysprosium, the researchers write in Scientific Reports.
Large rare-earth deposits are found in many nations, but China dominates the field—supplying roughly 90 percent of the minerals. That’s, in part, because rare-earth element production is often a byproduct of other mining operations, but China also has businesses to process the minerals into materials usable in industrial applications. China extracted around 150,000 tons of rare earths in 2016, according to industry experts, Japan Times reports.
China has also demonstrated a willingness to artificially reduce supply. For instance, in 2010, China pushed rare-earth prices up as much as 10 times by cutting its export quota on 17 elements by 40 percent from the previous year. Bejing said it wanted to clean up a polluting industry, although the move conspicuously also came at a time of heightened diplomatic tension with Japan, and left Japanese manufacturers—the world’s second-largest consumer of these minerals—with serious supply shortages. Japanese manufacturers have since lowered the amount of rare-earth metals they use in batteries and motors. It’s worth noting that the World Trade Organization (WTO) eventually ruled that China’s export restrictions on rare-earth elements were inconsistent with its obligations as a WTO member.
It’s also worth pointing out that rare-earth elements require what, frankly, is a laborious and sometimes hazardous extraction process. To separate the elements from the ore which contains them, the materials are repeatedly dissolved in solutions of acids, then filtered, and dissolved even more. Rare-earth ore goes through these steps hundreds of times, and for each new mining location, the concentration of the necessary acids must be recalculated to specifically target the precise impurities in the soil. In many respects, it can be argued that the process isn’t so much about removing rare earths from the mix, but more accurately is about removing everything else.
As for the new Japanese find, isolating rare-earth minerals from mud hundreds of meters underwater undoubtedly will be both expensive and time consuming, and the researchers do stress the importance of the efforts to develop efficient and economic methods to collect the deep-sea mud. That said, the team explains they have also developed an efficient method to separate valuable elements from others in the mud.
“The enormous resource amount and the effectiveness of the mineral processing are strong indicators that this new (rare-earth rich mud) resource could be exploited in the near future,” the researchers write.
It will be interesting to follow research about this new rare-earth find.