Japan's boundless supply of rare earths can blunt China's dominance

But the deposits, 6,000m below the ocean surface, are costly and difficult to mine

- Walter Sim Japan Correspondent

Deep beneath the waters off Japan's easternmost island of Minamitorishima lies what scientists have described as a "semi-infinite" trove of rare earths that can last the world for centuries.

With vast deposits of 16 million tonnes of high-quality rare earths, the world's third-largest reserve can significantly cut into China's dominance.

The snag is that they are costly and difficult to mine because of the deep depths of the sea - expected to be up to 6,000m below the ocean surface - around Minamitorishima.

China, which holds a near-monopoly in the processing of these critical minerals, has used trade restrictions and export controls on them for geopolitical ends.

Rare earths refer to 17 metallic elements that are needed to manufacture everything from electric vehicles (EVs), aircraft engines and wind turbines to medical lasers, semiconductors and military weapons systems. They are classified by atomic weight as "light", "medium" or "heavy" and, generally, they are more valuable the heavier they are.

In April, China imposed export curbs on seven types of heavy and medium rare earths that are sourced almost entirely from within the country, including dysprosium and terbium that are used widely in EVs.

On Oct 9, Beijing imposed sweeping new restrictions while adding five more elements to the list.

US Trade Representative Jamieson Greer has described the move as a "global supply-chain power grab", while Treasury Secretary Scott Bessent told Fox Business that China has "pointed a bazooka at the supply chains and the industrial base of the entire free world".

US President Donald Trump reacted by threatening to impose an additional 100 per cent tariff on Chinese imports.

But scientists have noted that the mineral deposits in waters around Minamitorishima, a remote atoll nearly 2,000km southeast of Tokyo in the northwestern Pacific, contain far higher concentrations of heavy and medium rare earths than in China.