In the practice of ore dressing for depression of sphalerite flotation ZnS04 or FeS04 in combinations with KCNNa2C03, Ca(OH)2 in quantities providing precipitation in the pulp, consisting of one or more compounds are used. P. A. Rebinder and coworkers in the study of the marginal angle of water on the anschliffs of sphalerite did not find depressing effect of zinc sulfate on both unactivated and pre-activated by copper ions surface of sphalerite. Currently, a number of authors believe that a possible cause of depression of sphalerite flotation is the adhesion of precipitation on the surface of mineral particles.