Comparison in Mineralization between Ferromanganese Nodules and Co-Rich Manganese Crusts in Pacific Ocean

The ferromanganese deposits in the deep-sea floor of the Pacific Ocean are classified as two types: polymetatlic nodule (hereafter shortened as nodule) and Co-rich crust (hereafter shortened as crust). The comparative research between.the nodule and the crust shows that several similarities and differences are present geochemically between them. Both the nodule and the crust consisting of manganese and iron oxide and hydroxide that contain some of transitional and divalent metal elements such as Co, Ni, Cu, Zn and Pb, have similar inner structures such as laminar, pillar or columnar, mottled and compact structure. However, conspicuous differences in chemical and mineralogical composition are present between the nodules and the crusts (Table 1).