This invention relates to a collector composition for the direct froth flotation of nonsulfide ores comprising a) 50-99 wt.-% of a mixture of fatty acids and b) 1-50 wt.-% of an N-acyl derivative of sarcosine of the formula (I) wherein R is a saturated or unsaturated hydrocarbon chain with 7 to 21 carbon atoms, wherein the mixture of comprises 10.0-35.0 wt.-% of fatty acid having a saturated C11 hydrocarbon group, 2.5-15.0 wt.-% of fatty acid having a saturated C13 hydrocarbon group, 10.0-25.0 wt.-% fatty acid having a monounsaturated C17 hydrocarbon group and 20.0-45.0 wt.-% fatty acid having a bisunsaturated C17 hydrocarbon group.