TOKYO -- The next major geopolitical tug-of-war could take place in the Earth's watery depths, with countries and companies looking to gain the edge in deep-sea mining.
Scientists estimate that billions of tons of manganese, iron, magnesium, titanium, potassium, cobalt and nickel can be found in ocean crusts and nodules, with some arguing that certain minerals are more abundant on the seafloor than on land.
