Iron-manganese nodules mineral

Iron-Manganese Nodules and Other Hydrogenous Minerals... 

The diffusive boundary layer plays an important role for the exchange of solutes across the sediment-water interface (Jorgensen 2001). For chemical species which have a very steep gradient in the diffusive boimdaiy layer it may limit the flux and thereby the rate of chemical reaction. This may be the case for the precipitation of manganese on iron-manganese nodules (Boudreau 1988) or for the dissolution of carbonate shells and other minerals such as alabaster in the deep sea (Santschi et al. 1991). For chemical species with a... 

Chukhrov, F.V., Gorshkov, A.I., Drits, V.A., Shterenberg, L.Ye., Sivtsov, A.V. and Sakharov, B.A., 1983. Mixed-layered asbolite-buserite minerals and asbolite in oceanic iron-manganese nodules. International Geological Review, 25 838-847. 

Considerable attention has been directed to Mossbauer spectra of iron-manganese nodules, which are marine mineral d osits with finegrained structure (36-41). 

A rich supply of manganese lies in nodules of ore that litter the ocean floors (Fig. 16.9). These nodules range in diameter from millimeters to meters and are lumps of the oxides of iron, manganese, and other elements. However, because this source is technically difficult to exploit, manganese is currently obtained by the thermite process from pyrolusite, a mineral form of manganese dioxide ... 

Nodules Mineral precipitates, such as iron-manganese oxides and glauconites, that form as roundish lumps. 

The iron hydroxide in manganese nodules cristallizes possibly as the mineral Goethite . The crystallization of Goethite is presumed to occur secondarily by drying and in the preparation of the manganese nodules. The primary iron hydroxide is amorphous. 

Giovanoli R. and Arrhenius G. (1988) Structural chemistry of marine manganese and iron minerals and synthetic model compounds. In The Manganese Nodule Belt of the Pacific Ocean Geological Environment, Nodule Formation, and Mining Aspects (ed. P. Halbach). Eerdinand Enke Verlag, pp. 20-37. 

The most abundant metals, which exist as minerals in Earth s crust, are aluminum, iron, calcium, magnesium, sodium, potassium, titanium, and manganese (see p. 62). Seawater is a rich source of some metal ions, including Na, Mg and Ca. Furthermore, vast areas of the ocean floor are covered with manganese nodules, which are made up mostly of manganese, along with iron, nickel, copper, and cobalt in a chemically combined state (Figure 20.2). 

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