Precise Pb isotope ratios are reported for five sedimentary-exhalative Pb-Zn-Ag deposits. Four deposits - HYC, Mt Isa, Hilton and Dugald River - show very little variation internally or among the group. The fifth deposit - Lady Loretta - exhibits a variation of = or <0.6% in the 207Pb/ 206Pb ratio for reasons yet to be determined. Gossan samples exhibit the same isotopic characteristics as fresh sulphides and are therefore equally useful in distinguishing these Australian shale-hosted deposits from the vein-style deposits at Lawn Hill and McArthur River, which are marked by variable and radiogenic lead isotopes. -G.J.N.