Rhenium and non‐radiogenic osmium in Australian molybdenites and other sulphide minerals by neutron activation analysis

Abstract Neutron activation analyses for rhenium and non‐radiogenic osmium abundances in molybdenites and other sulphide minerals, mostly from Tasmanian localities, indicate that the non‐radiogenic osmium content in these minerals is very low and is less than 0#lb005 ppm. When compared with other recently published data, the rhenium abundances in molybdenites from Tasmania are significantly lower than those occurring within the rocks of the Tasman Geosyncline in Victoria, New South Wales and Queensland. In both Tasmania and the Australian mainland the rhenium abundances are log‐normally distributed. Within Tasmania, at least, molybdenites with relatively high rhenium contents do not seem to be necessarily associated with copper mineralisation as Riley (1967) has suggested.