Quantitative analysis of collectors adsorbed onto mineral surfaces using headspace analysis gas-phase infrared spectroscopy (HAGIS) is explored for the galena/xanthate system. Four possible standards have been evaluated: sodium isopropyl xanthate, Pb-isopropyl xanthate, galena (PbS) conditioned with sodium isopropyl xanthate, and a Pb-sulphide ore conditioned with sodium isopropyl xanthate. All gave linear calibrations. For practical use, ores as standards are suggested. (C) 2004 Published by Elsevier Ltd.