Why Is Japan Digging The Ocean Floor At 6 Km Depth; Is China’s Rare Earth Monopoly Faces Its Biggest Threat?

Japan is doing deep-sea mining of rare earth-rich mud to secure critical minerals, cut reliance on China and change global supply chains.

Japan Deep Sea Mining: To cut its dependence on China and strengthen domestic supply chains, Japan is preparing to extract rare earth elements from deep-sea mud by 2027. The plan involves drilling nearly 6,000 metres below the ocean surface, lifting seabed sludge and transporting it to the mainland for processing.

Rare earth minerals have become the backbone of modern life. From electric vehicles and advanced weapons to semiconductors and cutting-edge electronics, these elements are at the heart of today’s most strategic industries. As demand rises, so do tensions around who controls their supply.

With China holding a dominant position, countries across the world are searching for alternatives. Japan has now placed a bet beneath the ocean floor.

Tokyo has drawn up a plan to extract rare earth elements from deep-sea mud by 2027. The objective is to reduce reliance on China and secure a stable and homegrown supply for industries that power Japan’s economy.

According to Nikkei Asia, Japan is targeting seabed deposits located around 6,000 metres below sea level. The process will involve lifting mud from the ocean floor and transporting it to the mainland, where valuable minerals will be separated and refined.

Tokyo’s focus is especially on elements such as dysprosium, a critical component used in automobiles and high-tech manufacturing. This matters much for a country whose automobile industry is among the largest in the world. Brands such as Toyota, Honda, Suzuki and Nissan depend on uninterrupted access to rare earth materials to keep production lines running and remain competitive globally.

The urgency behind this strategy can be traced back to a moment of reckoning in 2010. During the Senkaku Islands dispute, China halted shipments of rare earth elements to Japan.

The move exposed how vulnerable Tokyo had become to supply disruptions. Since then, Japan has worked to diversify its sources. Over the past decade, it has managed to cut its dependence on China by roughly one-third.

Globally, Beijing still controls around 70 per cent of rare earth supply and close to 90 per cent of refining capacity. To loosen this grip, Tokyo invested in Australian mining company Lynas, ensuring long-term access to rare earths outside China’s control. Under this arrangement, mining takes place in Australia, while refining is carried out at a plant in Malaysia.

According to The New York Times, until recently, this facility was the only major rare earth separation plant operating outside China.

Now, Japan is pushing the frontier even further, deep into the ocean. Under its Strategic Innovation Promotion Programme (SIP), a specialised facility will be established on Minamitorishima, an island in the Ogasawara island chain. Here, mud lifted from the seabed will undergo initial separation before being shipped to mainland Japan for final processing.

Nikkei Asia reports that trial mining could begin as early as January-February 2026. During this phase, the Japan Agency for Marine-Earth Science and Technology will deploy a deep-sea research vessel. Using pipes, small quantities of seabed mud will be brought to the surface to test the feasibility of the process.

A full-scale demonstration of the project is planned for February 2027. At Minamitorishima, nearly 80 per cent of the water will be removed from the extracted mud. The remaining material will then be transported by ship to Japan’s mainland, where rare earth metals will be produced.

SIP Director Shoichi Ishii has said the project’s goal is to successfully demonstrate the entire extraction process and assess whether it makes economic sense on a large scale. Nikkei Asia says that Japan has allocated around 16.4 billion yen, roughly $105 million, for the project.

Experts believe that if Japan succeeds, the impact could reach far beyond its shores. A viable deep-sea rare earth supply would strengthen Tokyo’s strategic independence and could alter the balance of power in the global rare earth market, an arena long dominated by China.