Manganese tungstates

The Wolframite Group. The wolframite group comprises iron and manganese tungstate minerals of varying composition. The iron tungstate up to a manganese content... 

At an elevated temperature, iron and manganese tungstates form a continuous solid solution series. Due to the fact that the temperature during mineral crystallization was sometimes below the limit of miscibility, ferberite and huebnerite can also be found side by side and not as a mixed crystal, as would be the case at correspondingly high temperatures. 

MnW04 MANGANESE TUNGSTATE 1062 NaB305 SODIUM TRIBORATE 1110... 

A mineral consisting of a mixed iron-manganese tungstate, (FeMn)W04, crystallizing in the monoclinic system the principal ore of tungsten. It commonly occurs as blackish or brownish tabular crystal groups, it is found chiefly in quartz veins associated with granitic rocks. China is the major producer of wolframite. 

Manganese tungstate MnW04 Acid or alkaline medium R-710,765, 825, oil acids Alcohols, pine oil. Aerosol surfactant ... 

Sal soda, see Sodium carbonate 10-water Saltpeter, see Potassium nitrate Scacchite, see Manganese chloride Scheelite, see Calcium tungstate(VI)(2—)... 

H. 8-Hydroxyquinaldine (XI). The reactions of 8-hydroxyquinaldine are, in general, similar to 8-hydroxyquinoline described under (C) above, but unlike the latter it does not produce an insoluble complex with aluminium. In acetic acid-acetate solution precipitates are formed with bismuth, cadmium, copper, iron(II) and iron(III), chromium, manganese, nickel, silver, zinc, titanium (Ti02 + ), molybdate, tungstate, and vanadate. The same ions are precipitated in ammoniacal solution with the exception of molybdate, tungstate, and vanadate, but with the addition of lead, calcium, strontium, and magnesium aluminium is not precipitated, but tartrate must be added to prevent the separation of aluminium hydroxide. 

Determination of tungsten as the trioxide (tannic acid-phenazone method) Discussion. Tungstic acid is incompletely precipitated from solutions of tungstates by tannic acid. If, however, phenazone (2,3-dimethyl-l-phenyl-5-pyrazolone) is added to the cold solution after treatment with excess of tannic acid, precipitation is quantitative. This process effects a separation from aluminium, and also from iron, chromium, manganese, zinc, cobalt, and nickel if a double precipitation is used. 

F,SCH, Methanesulfonic acid, trifluoro-iridium, manganese and rhenium complexes, 26 114, 115, 120 platinum complex, 26 126 OiFeCgH, Iron, acetyl dicarbonyl (if -cyclopentadienyl)-, 26 239 0,FeN2C2 Hll(, Iron, tricarbonylbis(2-isocy-ano-l,3-dimethylbenzene)-, 26 54 0.iMoNaCHH5-2 C4H ,02, Molybdate 1 -), tricarbonyl(T) -cyclopentadienyl)-sodium, compd. with 1,2-dimethoxy-ethane-(l 2), 26 343 0,NaWC H5-2 C4H ,02, Tungstate(l -), tricarbonyl(ris-cyclopentadienyl)-... 

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