Water From Iron Reduction

Excel spreadsheet. Great for experimental petrologists. If a silicate melt is “fused” or “pre-melted” at the same oxygen fugacity that the experiments are ultimately run at, the ratio of ferric to ferrous iron in the melt will remain unchanged. If, however, the melt is fused in air and then run at more reducing conditions, some of the Fe2O3 will be reduced to FeO and will add water to your melt in the process. Use this tool to calculate just how much water was added to your melt due to the reduction of iron during your run. Only works if pre-run fO2 is in air (i.e. all iron is Fe2O3 before run), but calculation can be made for any experimental fO2. References: Kress & Carmichael (1991); B. R. Frost in Mineralogical Society of America “Reviews in Mineralogy” Volume 25. Version 1.