Provided is a method of making improved brightness kaolin clay from an aqueous kaolin clay slurry in which the primary active dispersant is a weak dispersant, at least including the steps of adding to the kaolin clay an effective magnet enhancer reagent wherein the magnet enhancer reagent comprises an aqueous solution of one or more magnetic oxides and one or more surface active agents; conditioning the kaolin clay; and performing high gradient magnetic separation on the conditioned kaolin clay to produce an improved brightness kaolin clay. The method is also applied to decreasing iron- and/or titania-containing impurities in a clay.