The dispersion-flocculation behaviour of synthetic mineral mixture using polymeric flocculants was investigated. Results reveal that flocculation of the separate minerals with 50 ppm causticised cassava starch occurred within the acidic pH region (pH 3-6) with maximum flocculation occurring at pH 5 and the optimum flocculation occurring within a narrow causticised starch concentration range of 20-40 ppm (hematite suspension), while the flocculation of silica suspension was found to be independent of starch concentration above 25 ppm. For the effective flocculation of the separate minerals, 75 ppm of polyacrylamide was found to be needed. It was established that for the hematite/silica mixture suspension, 50 ppm causticised starch concentration in the acidic pH region (pH 3-6) gave the best result. Electrokinetic studies conducted to study the mechanisms involved provided indication for the shift of shear plane. Based on the data gathered in the study, it is concluded that causticised cassava starch is a better flocculant for the selective flocculation of hematite/silica mixture suspension than polyacrylamide.