NASOWHI, SHAHXNE ADD MAGEE~ have indicated the usefulness of ferroina in the separation of gold fram many other metals (Co, Ni, Cu, Mn, Fe, 2% and Cr). In &tempting to extend their procedure to small amounts of gold, the fact that the spectral densities for ferroin and the iron r,xo-phenanthroline tetrabromoaurate complex, [AuBr4]2CI;e(r,ro-phen)sJ, are similar for the peak at 5x3 nm becomes a serious limitation, since any carry-over of ferruin will result in high and probz~bly variable blanks, One of the experiments in an attempt to improve the sensitivity of the colorimetric procedure was the use of bathophenanthroline in the chloroform extraction phase af the CAuBr*~zfFc(x,ro-phen)3j to see if this would result in the formation of the iron bathophenanthroline complex, The staichiometric relationship of gold to iron is 7:r by weight. The factor for iron bathophenanthroline in 5-cm cells is x2.1 pg EXPERXMENTAL Ferru& solu~~'o~* (O.OOZ~ M). Made by dilution of ferroin (0,025 &f). Rat~zo~Renantkva~~~s* (t3.~15*/~). Made by dissolution of 0.10 g of the reagent in 200 ml of absolute ethanol. Spectruphotometer (Bausch and Lamb, Precision) with s-cm ceb. * Obtained frtxn G. Frederick Smith Chcmicatl Co.