OREAS 32

Base metal sulphide ore reference material OREAS 32 is a composite of Pb-Zn-Ag ore and “blue quartz” rock from Minerals Mining and Metallurgy Ltd’s South Mine at Broken Hill in western New South Wales and copper concentrate from Renison Goldfields Consolidated Ltd’s Mount Lyell Mine in Queenstown,Tasmania. The Broken Hill South Mine is in strongly deformed, high grade metamorphics of the Lower Proterozoic Willyama Complex. The ore and blue quartz Lode occur within a distinctive unit known as the lode horizon consisting of alternating ore lenses and sillimanite gneiss and quartzite layers.
The major economic minerals are sphalerite and galena in assooiation with pyrrhotite, chalcopyrite, arsenopyrite and loellingite. The Mount Lyell mineralisation is contained within a series of sheared and altered Cambrian acid lavas, intermediate to acid pyroclastics and cherts. They range from disseminated, low grade pyrite-chalcopyrite ores to richer bornite-chalcopyrite ores with massive and banded pyritic ores towards the top of the sequence.