The effects of Pb(II) ions on the flotation of hemimorphite was investigated by micro-flotation tests, zeta-potential measurements, solution chemistry and Fourier transform infrared spectroscopy. The micro-flotation results indicated that the Pb(II) effectively improved the flotation of hemimorphite minerals. Good floatability of minerals was obtained in the pH region 7 to 9. Adsorption/precipitation of the hydrolyzed species of lead cations occurred in this pH region, these species promote sodium oleate adsorption and from lead oleate on the surface of hemimorphite. (C) 2016 Elsevier Ltd. All rights reserved.