Microbeam AMS measurements of PGE and Au trace and osmium isotopic ratios

The microbeam Accelerator Mass Spectrometry (AMS) system, AUSTRALIS (AMS for Ultra Sensitive TRAce eLement and Isotopic Studies) at CSIRO Heavy Ion Analytical Facility (HIAF) has been used to measure trace levels of precious metals, the platinum group elements (PGE) and Au, from an assortment of geological and meteoritic samples with spatial resolution of 30 micrometres. For Au, detection sensitivity as low as sub parts per billion has been obtained, which will be of great benefit in studies of ore deposit mineralogy and mineral processing. We have also demonstrated the facility for osmium isotope measurements in meteorite samples, opening up the possibility of widespread use of the Re-Os system in exploration programs.