Centuries of underwater volcanic activity have blanketed the ocean floor in precious metals. Now, with the aid of the world’s most powerful excavation machines, a company called Nautilus Minerals is set to begin extracting those metals from the first large-scale deep-sea mine. The Toronto-based firm teamed up with the deep-sea trencher specialist Soil Machine Dynamics to build three remotely operated machines. Hybrids of land excavators, sea robots, and vacuum cleaners, they will work together to harvest rock from the seafloor, smash it into bits, and then send it to the surface.

Last year, Nautilus won a 20-year lease from Papua New Guinea to mine in the Bismarck Sea. The company’s first customer, Tongling Nonferrous Metals Group of China, has already claimed the entire contents of the first site, Solwara 1, which is roughly the size of 21 football fields and contains 240,000 tons of copper and 25,000 pounds of gold, plus silver and zinc. Although metal prices fluctuate, the total take could approach $3 billion. Nautilus plans to put its machines to work by the end of next year.

1. From a ship on the surface, a crew sends down remotely operated vehicles (A) to do final surveys and help install 14 sonar buoys, which will track the three mining machines to within 1.5 feet.