1. Surface & Aqueous Geochemistry Group; Department of Geological & Environmental Sciences; Stanford University; Stanford CA USA
2. Center for Applied Geoscience; Eberhard KarlsUniversity of Tuebingen; Tuebingen Germany
3. Mineral Resources Program; U.S. Geological Survey; Menlo Park CA USA
4. Department of Chemical Engineering; Stanford University; Stanford CA USA
5. Department of Photon Science and Stanford Synchrotron Radiation Lightsource; SLAC National Accelerator Laboratory; Menlo Park CA USA