The stash of rare metals sits in a 965-square-mile patch in the Pacific Ocean near Minamitorishima Island in Japanese waters, about 1,150 miles southeast of Tokyo.
The rare-earth metals are used to make products such as batteries, mobile phones and electric cars.
China owns most of the rare-earth metals but the discovery could have a huge impact on manufacturers across the globe.
On the other hand, Japan is resource-poor and relies heavily on the manufacturing abilities of its Asian neighbours.
The report, published in Scientific Reports, says that the patch contains 16 million tons of rare-Earth oxides – equivalent to 780 years’ worth of yttrium supply, 620 years of europium, 420 years of terbium and 730 years of dysprosium.
It added that the discovery “has the potential to supply these metals on a semi-infinite basis to the world”.
The study reads:” Rare-earth elements and yttrium (REY) are critical materials to many leading-edge technologies due to their unique physical and chemical properties.
“Applications of REY span a wide range, including hybrid vehicles, rechargeable batteries, wind turbines, light emitting diodes, compact fuorescent lamps, screen display panels, and many medical and military technologies.”
The Wall Street Journal reports that the discovery by Japanese scientists means that the Land of the Rising Sun could overhaul China to become the world leader in producing the materials, which would be a massive boost to their economy.
However, extracting the metals will be an expensive project.
The WSJ reports that a consortium of Japanese government-backed entities, companies and researchers will conduct feasibility tests over the next five years.