Local distribution of cobalt and selective enrichment of platinum in oceanic ferromanganese nodules

The distribution of cobalt in the structure of ferromanganese nodules (FMN) was studied using beta-autoradiography. In some cases, the content of element increased in the outer part of the nodules, or in thin layers within the nodules. Layered type of cobalt distribution in FMN indicates changing conditions in deposition during their formation, in particular also the living conditions of microorganisms known to inhabit oceanic ferromanganese nodules. Experimental studies suggested that colonies of micromycetes living at the surface of the nodules can have an important impact on the selective accumulation of platinum and other elements in FMN.