Japan announced on Friday that medium and heavy rare earth elements accounted for approximately 54% of the rare earth content found in deep-sea mud recovered from the Pacific Ocean floor, marking a significant step in the country's efforts to secure domestic supplies of critical minerals amid tightening Chinese export controls. The discovery stems from a month-long mission completed in February by the government-backed deep-sea drilling vessel Chikyu, which recovered approximately 50 tonnes of mud from a depth of around 6 kilometres near Minamitori Island, located approximately 1,900 kilometres southeast of Tokyo. The expedition is described as the world's first successful continuous recovery of rare earth-bearing seabed mud at such depths.
Kazushige Kikuchi, project manager at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), told Reuters that the trial is expected to verify the feasibility of domestic rare earth production. A comprehensive assessment of the project's commercial potential is scheduled to be completed by March 2028. Analysis of the recovered material identified several strategically important elements, including yttrium, used in aerospace, energy and semiconductor applications; gadolinium, employed in magnetic resonance imaging and other high-tech products; and dysprosium, an essential component in high-performance magnets for electric vehicles.
The project carries significant geopolitical implications for Japan. Beijing imposed export controls on some heavy rare earths and related magnets in April 2025, later tightening restrictions specifically on shipments to Japan in January 2026 and twice more the following month. These moves have intensified Japan's urgency to develop alternative domestic supply chains for materials critical to defence equipment, electric vehicles and advanced technologies.
Despite the positive findings regarding rare earth composition, Japan's government did not disclose the overall size of the deposit or the concentration levels of rare earth material within the recovered mud. Officials noted that the limited duration and geographic scope of the sampling programme provided insufficient data for a broader resource estimate at this stage. Source: Mining.com, Reuters, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), July 24, 2026.
Source: mining.com