Japan to begin deep-sea test mining of rare-earth mud near Minamitori Island

Japan will carry out test mining of rare-earth-rich mud from the deep seabed off Minamitori Island, about 1,900 kilometres (1,180 miles) southeast of Tokyo, from January 11 to February 14, the head of a government-backed project said on Tuesday.

The operation will be the world’s first attempt to continuously lift rare-earth-bearing mud from a depth of roughly 6,000 metres onto a vessel.

Like its Western allies, Tokyo is seeking to secure stable supplies of critical minerals as China — the dominant global supplier of rare earths — tightens export controls.

“One of our missions is to build a supply chain for domestically produced rare earths to ensure a stable supply of minerals essential to industry,” said Shoichi Ishii, programme director of the Cabinet Office’s national platform for innovative ocean development.

The Japanese government is pushing the national project as part of broader efforts to strengthen maritime and economic security.

The January test will focus on linking the deep-sea mining system and confirming its capacity to lift about 350 metric tonnes of rare-earth mud per day. Environmental impacts will be closely monitored both on board the research vessel and on the seabed throughout the operation.

No production targets have yet been set, but if the trial proves successful, a full-scale mining test is planned for February 2027. The government-funded project has spent around 40 billion yen ($256 million) since 2018, though estimated reserves have not been disclosed.

Ishii also revealed that during rare-earth surveys conducted within Japan’s exclusive economic zone (EEZ) around Minamitori Island between May 27 and June 25, a Chinese naval fleet entered the waters on June 7.

“We feel a strong sense of crisis that such intimidating actions were taken, despite our activities being limited to seabed resource surveys within our EEZ,” Ishii said.

In response, China’s foreign ministry said its naval activities were in accordance with international law and conventions, and urged Japan to “refrain from hyping up threats and provoking confrontation,” according to a reply to Reuters’ request for comment.