TOKYO — Seabed mud retrieved from waters near Minamitorishima contains high concentrations of medium-to-heavy rare earth elements, Japan's Cabinet Office announced Thursday, potentially bolstering the country's bid to diversify its supply chains for critical minerals.
The Japan Agency for Marine-Earth Science and Technology said about 54 percent of the rare earths found in the mud were medium-to-heavy varieties, with yttrium comprising 29.9 percent of the total — the largest single component — alongside gadolinium at 4.9 percent and dysprosium at 4.6 percent. The drilling vessel Chikyu recovered approximately 50 tonnes of mud from a depth of 6,000 metres within Japan's exclusive economic zone during a survey conducted in January and February this year.
The Cabinet Office is planning a large-scale test extraction beginning in February 2027, with commercialisation targeted from fiscal 2028 onward pending a profitability assessment. Prime Minister Sanae Takaichi noted the findings on social media on Thursday.