Synchrotron data - Cleverley 3648 (Sep 2011) - Mapping the signals of in-situ redox changes during gold precipitation in high-grade gold deposits

Using the unique X-ray Fluorescence Mapping beamline coupled with the Maia-384 detector we plan to map large area (100-500 μm) XANES spectra of important redox species (As, Cr, V and Fe) within the mineral hosts (pyrite, biotite, ilmenite) for naturally occurring hydrothermal gold. This will for the first time allow the spatial determination of a) the coupled changes in redox state of trace elements and allude to the fundamental processes of gold deposition and, b) provide evidence for the redox state of important gold complexes in high grade natural gold deposits. We propose to analyse natural high-grade gold bearing quartz vein material from world-class systems at St Ives, Agnew, Sunrise Dam and Plutonic that have been well characterised by Scanning Electron Microscopy and/or X-ray Fluorescence Mapping (Hough et al, 2009).