Japan's Deep-Sea Rare Earth Drilling Test Succeeds, Commercial Viability Assessment Expected by 2028
N.R. Finch
Japan successfully extracted rare-earth-bearing mud from 6,000 meters below the Pacific near Minamitorishima, plans a larger trial next February, and will decide on commercialization by March 2028 — a milestone in its decade-long push to break dependence on Chinese supply.
What did they pull up from 6,000 meters down?
Earlier this year, Japan drilled at 6,000-meter depth near Minamitorishima and recovered roughly 50 metric tons of seabed mud confirmed to contain yttrium, gadolinium, dysprosium, and neodymium.
These four elements feed semiconductors, nuclear-reactor control rods, EV components, and high-performance magnets — spanning the chip-to-defense supply chain.
The team reported no significant hazardous or radioactive materials, but did not disclose the actual volume of rare earths extracted. This means → the test proved "we can reach them," but "how much we can get" remains unanswered.
How large is the deposit?
Minamitorishima sits roughly 2,000 km southeast of Tokyo in a remote stretch of the Pacific. The surrounding seabed is estimated to hold about 16 million tons of rare-earth-rich mud.
In plain terms = that ranks as the world's third-largest rare-earth resource. If extraction proves economic, Japan would own a domestic reserve beholden to no other country.
But mining at 6,000 meters is far harder than on land. A large deposit does not guarantee low-cost recovery — and that is exactly what the next phase of testing must answer.
What comes next, and on what timeline?
Japan's Cabinet Office and the Japan Agency for Marine-Earth Science and Technology plan a larger-scale trial in February next year at the same site, aiming to validate the full extraction → separation → refining process at industrial scale.
A decision on whether commercial production is economically viable is expected by March 2028.
This means → between "the lab can do it" and "a factory can profit from it" lies nearly two years of validation. A technical milestone is not the same as a commercial one.
Why is Japan accelerating now?
China accounts for roughly 70% of global rare-earth mining output and nearly 90% of refining capacity. After Beijing imposed export controls on select rare earths in April 2025, prices of dysprosium and terbium surged.
Australian miner Lynas — one of the few companies mining and refining rare earths outside China — recently raised the projected cost of its new Malaysian facility by $80 million, partly because China restricted equipment sales to foreign producers. This reflects a squeeze not just on raw materials but on the upstream equipment needed to process them.
The International Energy Agency warned that full enforcement of China's export controls could put $6.5 trillion in downstream output — across autos, electronics, defense, and transport — at risk outside China.
How much "prior experience" does Japan have with rare-earth risk?
Japan was among the first countries to feel the strategic weight of China's rare-earth dominance — it suffered a supply cutoff during a 2010 diplomatic dispute.
Since then, Japan has diversified sources, built strategic stockpiles, and expanded recycling, putting it ahead of most advanced economies in reducing rare-earth dependence on China.
Put simply = this deep-sea test is not a cold start. It is the latest step in a decade-plus de-risking strategy — but from a successful test to actual commercialization, the road is not yet complete.
Content is for reference only, not financial advice.