Historically, there have always been places on Earth that seemed impossible to reach: the origin of the Nile, Antarctica, the summit of Everest…, but we have managed to set foot on all of these “impossibles”. Only one resists us: the deepest sea depths. At almost 6,000 meters below the surface of the ocean, sunlight has disappeared thousands of meters ago, the pressure is hundreds of times greater than what we endure on the surface and the seabed is in permanent darkness. But Beyond exploration, what have we lost there? Lost… nothing, quite the opposite: there we can find critical minerals and the United States and Japan are diving into their search.
The two countries are promoting plans to develop what could become one of the deepest underwater mining operations on the planet, near the remote Japanese island of Minamitorishima in the Pacific. The deposits contain rare earths and other strategic minerals that could help reduce dependence on Chinacurrently dominant both in the extraction and, especially, in the processing of these elements.
At 6,000 meters deep, The water pressure is around 600 atmospheres. Every square centimeter of any machine receives enormous pressure and there is no possibility of a human being working there directly. Everything would have to be done using machines capable of operating miles away from their operators.
And yet, Japan has already shown that it is possible to get there. In February of this year, a mission from the Japanese agency JAMSTEC (Japan Agency for Maritime-Terrestrial Science and Technology) achieved recover rare earth-rich sediments from about 5,700-6,000 meters deep in front of Minamitorishima. And there were rare earths there.
The so-called rare earth elements are a set of 17 chemical elements fundamental to much of modern technology. They appear in permanent magnets, electric motors, wind turbines, electronics, defense systems and numerous advanced technologies. AND Some of the deposits around Minamitorishima are especially interesting. because they contain heavy rare earths, some of the most difficult to obtain and process.
Japan estimates that the area has extraordinary resources. Of the total set of rare earths present in the mud, 54% corresponds to medium and heavy mass rare earths. The remaining 46% corresponds to light rare earths. The 17 rare earth elements known to date are usually divided, in a simplified way, into light and medium/heavy. The latter include elements such as yttrium, gadolinium and dysprosium, which are of special industrial interest. That is, not all rare earths have the same strategic value. And 54% of those found in the mud on the underwater bed are of high value.
The American and Japanese governments have pointed out that these deposits could meet industrial demand for centuries, although that statement refers to estimated resources and does not mean that they can be economically extracted in those quantities. And here appears the real reason for the race, because The problem is not finding them, it is extracting them.
The first obstacle is to lower a machine six kilometers, have it collect the sediment and then pump it to the surface through a pipe that must support its own weight and the enormous pressures of the environment. And the entire system must operate thousands of meters from the ship that controls the operation. The Japanese experiment of 2026 demonstrated precisely one of the fundamental elements: recover rare earth-rich sediments from that depth. But recovering a sample and extracting minerals industrially are two completely different things.
Here appears the other side of the story. The ocean floor is one of the least known ecosystems on the planet. At these depths live organisms adapted to extreme conditions, with low temperatures, permanent darkness and very limited food availability. Extracting sediment means physically altering that environment. Furthermore, the operations themselves can generate clouds of sediment that move through currents and affect areas far from the place where the machinery works. That’s why Underwater mining has been causing intense scientific and environmental debate for years.
The argument in favor is powerful: obtain minerals necessary for electrification, electronics, energy and defense without depending on certain suppliers. The argument against it is also: we still know very little about the ecosystems that we could alter. And there is another issue: that a deposit contains a huge amount of an element It does not automatically mean that it is profitable to extract it. The irony of this story is that, although rare earths are essential to building an increasingly technological and electrified world, to obtain them we could end up sending enormous machines to the darkest, most remote and extreme place on the planet. The most unknown and unexplored region until now.