This paper reports potato and corn starch based dual polymer flocculation of partially liberated complex ooidic iron ore. Corn starch selectivity for hematite, lost due to incomplete liberation of hematite and the presence of 16 ppm Ca2+, 3 ppm Fe3+, and 1 ppm Mg2+ polyvalent metal ions, was improved by dual polymer flocculation when the induction order of potato starch followed by corn starch was used. The initial feed grade of 41% Fe was improved to 46.2% with a recovery of 49.3% Fe after the addition of 40 ppm potato starch and 30 ppm corn starch to the iron ore slurry. In our case, potato starch has been found to behave mainly as a selective polymeric dispersant rather than as a flocculant The paper also discusses the possible occurrence of all the adsorption mechanisms involved in the flocculation of quartz and gangue minerals in the presence of polyvalent metal ions. (C) 2013 Elsevier By. All rights reserved.