Mangaanknol
Manganese nuts are widely found in many oceans-occurring tubers consisting of a mixture of iron and manganese oxide (and a large number of other metals and other elements in lower concentrations) which have grown very slowly over the course of millions of years . They occur widespread in deep waters where a very low sediment deposition exists. In some places 70% of the ocean floor is covered with it. The total amount of manganese lying on the seabed in this way is immense; However, due to the high depth and the long distances, it has not been possible to gain this natural resource economically.
In the sixties and seventies of the last century, a lot of research has been done and the presence of these tubers was one of the driving forces in the development of the UN Maritime Convention to define the legal status of fishery companies and governments of countries bordering on tubers containing water, which are mostly outside the territorial waters.
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