Not known for its raw material endowment, Japan could now be in a position to establish a substantial rare earths reserve and drastically reduce its dependence on imports from China, currently the world’s most active producer and consumer of rare earth elements.
As a country, Japan could achieve this feat courtesy of a new discovery near Minami-Tori-shima, an island around 2,000km from its south-eastern coastline.
The discovery of a potentially large rare earths resource locked up in deep-sea mud was made in 2013, but its sheer size and the ability to make the discovery economically viable has only been made earlier this year after scientists analysed samples and conducted a range of laboratory tests.
According to research published earlier this month, samples taken from deep-sea mud contained extremely high amounts of various rare earths, with some as high as 22,000 parts per million.
The authors said that four rare earths in particular — yttrium (Y), europium (Eu), terbium (Tb) and dysprosium (Dy) — were found to have substantial reserves lasting hundreds of years.
“The research area was estimated to be able to supply Y, Eu, Tb, and Dy for 780, 620, 420, and 730 years, respectively, and has the potential to supply these metals on a semi-infinite basis to the world,” according to the authors of the research paper.
The research paper states that the Japanese discovery site contains around 16 million tonnes, although the precise quality and contained amount of rare earths is disputable based on the cut-off level.
After subjecting samples to a “hydrocyclone separator”, a device that separates light and heavy rare earths through the use of a centrifuge, scientists were able to recover biogenic calcium phosphate grains containing rare earth elements and yttrium (REY) content of up to 22,000ppm, possibly the largest concentration of rare earths anywhere in the world.
Why rare earths and why now
REY materials are critical to many leading-edge technologies due to their unique physical and chemical properties.
Growing supply shortages for critical metals including REY have spurred great interest in commercial mining of deep-sea mineral resources by net importer countries such as Japan.
Applications of REY include hybrid vehicles, rechargeable batteries, wind turbines, light emitting diodes, fluorescent lamps and bulbs and screen display panels.
In effect, rare earths constitute a small but essential component of the mass of new products that are expected to become ever-more ubiquitous in modern high-tech societies.
REY applications, especially in renewable energy technologies and electronics, has driven up the demand for the essential metals in recent years, with lithium and cobalt grabbing the headlines and the lion’s share of the headlines and exploration efforts.
Not so rare
However, there is some evidence to dispute the largesse of Japan’s discovery.
According to supplementary research published by Holger Paulick and Erika Machacek, resources outside of China reached a total of 98mt contained total rare earth oxides in 2015 with the majority located in Canada (38mt), Greenland (39mt) and Africa (10.3mt).
China accounts for over 80% of rare earths supply and more than 66% of global demand in 2017. Production outside China is sparse although it is an Australian company that’s leading the charge.
Major rare earths producer Lynas Corp (ASX: LYC) operates the Mount Weld mine in Western Australia and produces over 5,000t of neodymium and praseodymium (collectively known as NdPr) per year.
Most of its output is committed to Japanese buyers interested in diversifying their sourcing from China, which makes the findings published by Nature Research all the more intriguing, especially from a long-term perspective.
Increasing rare earth prices and the resolve to remove Chinese dependence have accelerated the development of rare earths projects outside China, with projects in Australia, Russia, Brazil, Canada, Burundi and Tanzania set to enter production by 2027.
Where to for Japanese rare earths?
The research paper states that six rare earth metals in particular (dysprosium, neodymium, terbium, europium, indium and yttrium) are most critical in the short term for clean energy technologies.
The paper also mentions that the REY-enriched deep-sea mud has “great potential as a rare earth metal resource because of the enormous amount available and its advantageous mineralogical features”.
The paper also stated that the research authors had “established a mineral processing procedure to greatly enhance its economic value” since the discovery in 2013.
The research team said that the “enormous resource amount”, combined with the “effectiveness of the mineral processing” techniques now available were strong indicators that this new REY resource “could be exploited in the near future”.