Abstract: A method for coating finely divided particles with one or more hydrophobic materials, such as waxes, in order to envelope each particle with a thin layer of material that entraps air adhering to the surface of the particle. Because of the entrapped air, the apparent density of the particles is decreased and their stability in aqueous suspensions is greatly improved. When applied to pesticides, this process produces mixtures that remain substantially in suspension for several hours after agitation, thus allowing more uniform and trouble-free application.