Japan identifies large share of rare earths in deep-sea mud off remote island

By the Editorial Team · Sunday, July 26, 2026

Japan has discovered that about 54% of the rare earth elements in deep-sea mud collected near Minamitori Island are medium and heavy types, extracted at a depth of around 6,000 meters during a February expedition. This finding supports Japan's plan to begin large-scale mining trials in 2027 to reduce reliance on Chinese exports and develop domestic production of critical materials for advanced technologies.

Japan has identified a significant proportion of medium and heavy rare earth elements in deep-sea mud collected from the Pacific seabed near Minamitori Island, about 1,900 kilometers southeast of Tokyo. The government announced that these elements make up approximately 54% of the total rare earth content in samples retrieved earlier this year, although it has not disclosed the exact quantities or extent of the deposits due to limited sampling scope and duration.

The findings come from a month-long expedition conducted in February by the Japanese scientific drilling vessel Chikyu, which successfully extracted rare-earth-rich mud from a depth of approximately 6,000 meters. This mission marked the first continuous recovery of such seabed materials from this depth worldwide.

Rare earth elements such as yttrium, gadolinium, and dysprosium were identified in the recovered 50 metric tons of mud. Yttrium has applications in aerospace, energy, and semiconductor industries; gadolinium is used in medical imaging and other advanced technologies; and dysprosium is essential for manufacturing high-performance magnets used in electric vehicles. The Cabinet Office’s national platform for innovative ocean development coordinated the analysis.

Japan’s efforts to explore seabed rare earth resources are motivated by the need to secure stable supplies amid increasingly restrictive export controls imposed by China, a dominant global supplier of heavy rare earth elements crucial to defense and automotive sectors.

Building on the initial success, Japan plans to conduct a large-scale mining trial in the same area starting February 2027. The month-long operation aims to extract up to 350 tons of seabed mud daily. Extracted mud will undergo dewatering processes on Minamitori Island before being transported to the mainland for testing separation, refining, and smelting technologies.

Kazushige Kikuchi, project manager at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), which operates the Chikyu, said the upcoming trial will assess the viability of domestic rare earth production. A comprehensive evaluation that includes the prospects for industrialization is expected to be completed by March 2028.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.