hAuxiliary material for Paper 2007PA001576 Opal (Zn/Si) ratios as a nearshore geochemical proxy in coastal Antarctica Katharine R. Hendry and Rosalind E.M. Rickaby Department of Earth Sciences, University of Oxford, Oxford, UK. Hendry, K. R., and R. E. M. Rickaby (2008), Opal (Zn/Si) ratios as a nearshore geochemical proxy in coastal Antarctica, Paleoceanography, 23, PA2218, doi:10.1029/2007PA001576. Introduction This data set includes six figures, one table, and one text file. In Table S1, Column 1 "experiment" describes experiment; (1) the samples are referenced to a single standard ("single"), (2) each sample is bracketed by a standard ("bracket"). Column 2 "calc-al-si" gives the calculated Al/Si ratio in g/g. Column 3 "meas-al-si" gives the measured Al/Si ratio in g/g. Column 4 "rsd-al-si" gives the relative standard deviation of the ratio. Column 5 "calc-zn-si" gives the calculated Zn/Si ratio in umol/mol. Column 6 "meas-al-si" gives the measured Zn/Si ratio in umol/mol. Column 7 "rsd-zn-si" gives the relative standard deviation of the ratio. 1. 2007pa001576-textS1.txt. Operating conditions for the Q-ICP-MS, blank and sample intensities, and standard concentrations. 2. 2007pa001576-ts01.txt The effect of drift correction on accuracy and precision. 3. 2007pa001576-fs01.tif Sequential dissolution of box-core opal samples. 4. 2007pa001576-fs02.tif Plots of Al versus trace metal intensities for cleaned opal during a series of dissolution experiments showing. 5. 2007pa001576-fs03.tif Yield experiments for Si, showing 100% yield and no loss of Si through the production of volatile compounds. 6. 2007pa001576-fs04.tif Measurement of (Zn/Si) of artificial opal solution. 7. 2007pa001576-fs05a.tif Within-analysis external reproducibility of ratio method assessed by simulating a run by measuring a reference standard. 8. 2007pa001576-fs05b.tif Long-term external reproducibility assessed by measuring a reference standard at intervals throughout a period of a year.