A novel technique has been employed by the U.S. Bureau of Mines to determine the zeta potential of particles for a far-reaching series of material types in a wide variety of baseline waters, both alone and with many different chemical additives. The materials tested ranged from naturally occurring Sioux quartzite and Tennessee marble to commercially produced magnesium oxide bricks. The waters tested ranged from ultrapure distilled, deionized water to municipal tap water and mine-site water. The chemical solutions tested included inorganic additives, such as aluminum chloride (alcl3) and sodium chloride (nacl); organic additives, such as dodecyltrimethyl ammonium bromide (dtab); and nonionic polymers, such as polyethylene oxide (peo). The results of precise zeta potential determinations have application in a large number of laboratory studies as well as in various mining and processing operations.