5 Flotation of metal ores
Metal-bearing ores can be classified as follows for the purposes of flotation :
“Class b” metal sulphides and “borderline” metals, in particular lead, zinc, copper, nickel, bismuth, antimony and mercury
Carbonates, sulphates and silicates of metals such as lead, zinc, copper, etc.
Polar salt-type minerals containing cations of alkaline earth metals such as Ca, Mg, Sr and Ba – e.g. scheelite, calcite, dolomite, magnesite, fluorite, apatite, celestine and barite
Metal oxides, arsenates, silicates and alumina silicates
Water-soluble salts of alkali and alkaline earth...