flotation process

Flotation process \Flotation process\
   A process of separating the substances contained in
   pulverized ore or the like by depositing the mixture on the
   surface of a flowing liquid, the substances that are quickly
   wet readily overcoming the surface tension of the liquid and
   sinking, the others flowing off in a film or slime on the
   surface, though, perhaps, having a greater specific gravity
   than those that sink.
   [Webster 1913 Suppl.]