The present invention relates to a process for treating non-sulfidic ores with a collector composition containing a primary and a secondary collector, wherein the primary collector is selected from the group of amphoteric and anionic surface active compounds and the secondary collector is an ethoxylated fatty acid wherein the average degree of ethoxylation is higher than 0 and less than 2, to collector compositions suitable for use in the above process, and to pulp comprising such collector compositions.