Mining companies are staking claims on the deep sea floor. Ballpark estimates suggest that hundreds of millions of tons of precious metals lace the ocean bottom, including gold, silver, copper, zinc, cobalt and a host of others. Deep sea prospectors, eager to mine the rich deposits of metals that go into everything from home wiring to iPhones, have already been granted contracts for 27 exploration plans covering more than 1 million square kilometers. The first mine is slated to break ground in 2018. As you can see in the video above, even as miners try to figure out the complex task of extracting the metals, some scientists worry we’re about to witness a gold rush that will destroy ecosystems we barely understand.