For decades, the global supply of rare earth elements has been shaped by a simple reality: most countries depend heavily on China for the materials that power electric vehicles, wind turbines, advanced electronics, and defence systems. Japan learned the risks of that dependence firsthand during supply disruptions in 2010. Now, attention is turning to a remote coral island nearly 1,900 kilometres south-east of Tokyo that few people have ever heard of.Minamitorishima, an isolated outpost surrounded by some of the deepest waters in Japan's exclusive economic zone, sits above what researchers describe as one of the world's largest known deposits of rare-earth-rich mud. Scientists estimate the seabed contains enough dysprosium and yttrium to satisfy global demand for centuries. To reach it, Japan is developing advanced autonomous underwater vehicles capable of operating 6,000 metres below the Pacific Ocean, opening a new chapter in the race for critical minerals. If successfully developed, the resource could strengthen Japan's supply-chain security while reducing reliance on overseas sources of strategically important rare earth elements.Why Minamitorishima's rare earth deposit could reshape global supply chainsAccording to the Ocean Policy Research Institute, the discovery traces back to research led by scientists from the University of Tokyo and the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). In a landmark 2018 study published in Scientific Reports, researchers identified more than 16 million tonnes of rare-earth oxides within deep-sea mud surrounding Minamitorishima. According to an article ‘The tremendous potential of deep-sea mud as a source of rare-earth elements,’ researched and published by the Research and Development Centre for Submarine Resources, the deposit contains enough material to supply the world with yttrium for approximately 780 years and dysprosium for around 730 years under current consumption levels.The researchers wrote that the resource has the "potential to supply these metals on a semi-infinite basis to the world". This attracted immediate attention because dysprosium is a critical component in heat-resistant permanent magnets used in electric vehicle motors, wind turbines, and military technologies.Unlike many terrestrial deposits, the Minamitorishima resource lies entirely within Japan's exclusive economic zone, giving the country direct control over exploration and future development.Japan's 6,000-metre deep-sea drone project aims to unlock the Pacific seabedFinding the minerals is only part of the challenge. The deposits lie nearly 6,000 metres below the ocean surface, where pressure exceeds 600 times that at sea level.JAMSTEC is therefore developing a new generation of autonomous underwater vehicles (AUVs) designed to survey vast areas of the seabed more efficiently. According to the agency, these robotic systems will help identify high-grade mineral zones and reduce the time needed to map potential extraction sites.The programme has already moved beyond theory. In early 2026, the scientific drilling vessel Chikyu (it means the Earth) successfully recovered rare-earth-bearing sediment from depths approaching 6,000 metres near Minamitorishima. JAMSTEC described the operation as the world's first successful retrieval of rare-earth-rich mud from such depths.Yoshihisa Kawamura of JAMSTEC noted in a Nature briefing:"Thus far, Japan is the only country in the world that has found rare-earth muds in the waters of their exclusive economic zone."The agency is targeting further large-scale demonstration projects before deciding whether commercial extraction is technically and economically viable.Why the race for deep-sea rare earths matters beyond JapanRare earth elements are not actually rare in Earth's crust, but economically viable deposits are far less common, and processing capacity remains concentrated in a small number of countries.According to the data compiled by the International Energy Agency, China currently dominates the global supply chain for heavy rare earths, including dysprosium, which is essential for manufacturing high-performance magnets. China’s stronghold extends beyond refining; two-thirds of global battery recycling capacity growth since 2020 has been in China. This has prompted governments worldwide to seek alternative sources amid growing demand from renewable energy, electric vehicles, robotics, and defence industries.Japan's deep-sea programme is therefore being watched far beyond East Asia. If extraction proves feasible, Minamitorishima could become one of the most significant non-Chinese sources of critical minerals ever discovered.The project also raises important environmental questions. Deep-sea ecosystems remain among the least understood habitats on Earth, and researchers continue to debate how large-scale seabed mining could affect marine life and sediment systems. JAMSTEC has stated that environmental monitoring forms part of its ongoing test programmes.For now, the island remains uninhabited and largely unknown. Yet beneath the waters surrounding it may lie a resource capable of influencing global technology supply chains for generations.Catch the latest world news and top headlines. Download the TOI App.