While commodities traders still work their way out of a historic slump, Japan is looking ahead to the next boom. According to Bloomberg News, next year a group of Japanese companies and government agencies will start mining minerals at a site 1,600 km southwest of Tokyo — and 1.6 km beneath the ocean's surface. It will be the first large-scale test of whether mineral deposits can be mined commercially from the seafloor.

The project is fairly bold. The seafloor is home to priceless deposits of minerals such as gold, copper and cobalt. And thanks to new technologies, it might soon be exploitable. That's potentially good news for miners and commodity speculators. But it poses some alarming challenges for the marine environment — and the economies that depend on it.

At least as far back as the 1960s, scientists have known that rich deposits of minerals could be found in metallic nodules strewn like stones across the deep seabed. In 1977, researchers discovered hydrothermal vents on the ocean floor, along with some of the richest ore bodies in the world. In both cases, though, slumping commodity prices and high extraction costs doomed exploitation efforts.