In Japan’s exclusive economic zone (EEZ), a deep-sea mining site near a remote island has yielded over 200 million tons of manganese nodules rich in rare metals, with cobalt content equivalent to Japan’s domestic consumption for about 75 years and nickel for approximately 11 years.
Tokyo University and a Japanese foundation announced this discovery at a joint press conference held on Friday (June 21) in Tokyo. In 2016, a research team from institutions including Tokyo University found manganese nodule deposits near Minamitori Island, the easternmost point of Tokyo’s Ogasawara Islands.
From April to June this year, the Japanese foundation conducted detailed exploration, confirming the presence of 230 million tons of manganese nodules at a depth of 5500 meters covering an area of around 10,000 square kilometers on the seabed. Based on analysis of samples collected, cobalt resources were estimated at 610,000 tons and nickel at 740,000 tons.
The Japanese foundation intends to collaborate with European and American companies possessing deep-sea manganese nodule extraction technology. The initial mining costs are expected to exceed 5 billion yen (approximately $31 million), primarily funded by the Japanese foundation. Tokyo University will continue to provide academic support for the project.
The team plans to commence trial mining in 2025, recovering thousands of tons of manganese nodules daily to supply Japan’s metal refining plants. The Japanese foundation also aims to establish a private joint venture company, targeting commercialization of the project as early as 2026.
Manganese nodules, also known as polymetallic nodules, are highly versatile strategic resources. These fist-sized nodules consist of iron and manganese oxides, containing around 20% manganese, less than 1% cobalt, and nickel. All three elements are used in battery production, including electric vehicle batteries.
Apart from manganese nodules, rich deposits of cobalt-rich crusts and rare earth mud, containing materials widely used in high-strength applications, have been found near Minamitori Island. However, the high costs and technical challenges associated with deep-sea mining and extraction make it an extremely demanding task.