Scheelite flotation process

A continuous process of separating scheelite from gangue in an ore, which process comprises grinding the ore with 4 to 10 grams of an alkali metal carbonate per kilogram of ore, selectively separating sulphide minerals present in a pulp of the ore, subjecting the pulp comprising desulfided pulp and pulp liquor to a rougher froth flotation stage to separate selectively scheelite into a rougher concentrate, said flotation being carried out in the presence of a paraffin oil, from 0.1 to 0.4 gram of a fatty acid or a soap thereof per kilogram of ore and from 3.2 to 5.5 grams of sodium silicate per kilogram of ore, wherein the ratio by weight of paraffin oil to fatty acid is in the range of from 0.5:1 to 2.8:1 and wherein the amount of oil, alkali metal carbonate and sodium silicate are so correlated that a stable height of froth is maintained on top of the pulp during said rougher flotation stage, and subsequent to said rougher flotation stage, treating the rougher concentrate in at least one cleaner stage to produce a float and nonfloat product portion followed by recycling the nonfloat portion from the cleaner stage to the rougher froth flotation stage, said rougher flotation froth being controlled by adjusting the sodium silicate level in the flotation to obtain a dissolved silicate level of about 0.8 to about 1.2 grams per liter of pulp and adjusting the initial alkali metal carbonate level according to the condition of the forth at such dissolved silicate level.