Abstract: A reagent and a method for using the reagent for treating a solid material disposed in a liquid medium and having an oxygen-controlled surface condition. The reagent includes a liquid hydrocarbon, a reducing material and an activator material. The liquid hydrocarbon has a specific gravity different from the specific gravity of the liquid medium. The reducing material is present in an amount sufficient to establish a reducing environment around the solid material for breaking the oxygen control on the surface of the solid material. The activator material is present in an amount sufficient to establish an electrostatic charge on the solid material after the oxygen-controlled surface condition has been broken. A more specific feature of the invention is directed to the method of flotation of extremely fine bituminous coal having an oxygen-controlled surface condition. The reagent is useful in froth flotation processes and in bath flotation and separation processes.