oped in (3-5). That permits the production of high� quality manganese concentrates from ore and ferro� manganese concretions of different composition, as well as slag and dust from manganesealloy produc� tion. In the concentrate, 93-94% of the manganese is extracted. The concentrate contains 59-64% Mn, 0.02-0.50% Fe2O3, 0.5-1.0% SiO2, 0.004-0.009% P, traces of S, 3-4% CaO, and 3-5% CaCl2. We know that ferromanganese concretions in the Pacific Ocean and the Gulf of Finland contain nickel (around 0.5%), cobalt (up to 0.27%), and other nonfer� rous impurities. In calciumchloride enrichment, these metals remain in the tailings, whereas nickel is an impor� tant alloying element. At the boundary of the Kemerovo region and the Altai region, deposits of manganese ore containing nonferrous impurities have been found. Table 1 presents the chemical composition of these ores (5). It follows from Table 1 that Sugul ore is lean, since the Mn content is no more than 20%. The Chumai ore has a relatively high Mn content but the phosphorus concentration is relatively high. Therefore, such ore, like ferromanganese concretions, cannot be used for the production of standard manganese alloys without preliminary enrichment. The present work is devoted to the thermodynamic analysis of the reaction between manganese and nickel oxides (individually and in a mixture) and chloride solutions. The same reaction is also investigated in laboratory conditions. For the leaching reactions