Hydrogenetic ferromanganese crusts are considered a faithful record of the isotopic composition seawater influenced by weathering processes continental masses. Given their ubiquitous presence in all oceans planet at depths 400–7000 meters, they form one most well-distributed and accessible records water-mass mixing climate. However, slow accumulation rate poor age constraints have to date limit...

To the Editor: A recent article in PNAS by Asikainen and Werle (1) reports on the occurrence and morphology of ferromanganese nodules found in a New Hampshire lake. The authors offer data on the shapes, banding, composition, and distribution of the nodules and crusts. They also state that my paper (2) claims that the morphology of such nodules is controlled by elemental concentrations and that ...

Sighter Induced Roll Magnetic Separation tests were conducted on a ferromanganese ore sample to determine the potential significantly upgrade Mn content and Mn:Fe ratio. The had ratio of 1.3 was comprised hematite, cryptomelane, pyrolusite, quartz, goethite braunite. Tests at 4.7, 2.3 1 mm top sizes revealed better separation Fe from sizes. This reflected liberation characteristics oxides both ...

The article presents an analysis of methods that can be used for low‑tonnage production ferromanganese, ferrosilicon and other ferroalloys in the conditions a machine‑building enterprise using its own waste, including dispersed. It is proposed to carry out rotary tilting furnaces (RNP) new generation, which have maximum efficiency when heating melting dispersed materials, allow active oxidation...