World demand for rare-earth elements and the metal yttrium—which are crucial for novel electronic equipment and green-energy technologies—is increasing rapidly. Several types of seafloor sediment harbour high concentrations of these elements.

As mining companies prepare to exploit the copper and gold in the seabed, the author explore the fate of the unique ecosystems around tectonic boundaries.

http://www.newscientist.com/article/mg21128193.700-deep-sea-gold-rush-mi...

Let's see if we can mine the ores around hydrothermal vents without destroying the marine habitat in the process. (Editorial)

http://www.newscientist.com/article/mg21128192.600-new-dawn-for-mining-a...

As Papua New Guinea gives go-ahead to a Canadian mining company to dredge its coastal seabed for minerals, critics say environmental assessments have been inadequate, local objections ignored and new species of life could be extinct before they have even been discovered.

Polymetallic nodules found on the deep seafloor (>4000 m water depth) have been recognized as an alternative source for certain metals, when land deposits get exhausted.