Minerals on the Ocean Floor.

The article reports that sea is one potential source of low cost minerals that remains virtually unexplored and untapped. Sea water was considered a lean ore except in the case of magnesium and other substances that are extracted from it. The most promising ore is manganese dioxide. In deep-sea sediments it takes such forms as grains, coatings on rocks and impregnations of porous materials. It occurs in a strange product of sea-water chemistry which is called manganese nodules.