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Hello, I’m trying to model precipitation of the uranium-bearing mineral, Swartzite (CaMg(UO2)(CO3)3•12(H2O)), from solution. When I equilibrate my ground water chemistry of interest using REACT and X1T, Swartzite is the only uranium-bearing mineral to be supersaturated (SI>0 [sI=0.45]). I’m using an updated thermodynamic database, that includes uranium data determined after the discovery of Ca2UO2(CO3)30 CaUO2(CO3)3-2and MgUO2(CO3)3-2 complexes by Bernhard in 1996. I can’t find appropriate kinetic rate constants for the precipitation and dissolution of Swartzite to include in my REACT and X1T models. I plan to include rate constants of an alternate uranium-bearing mineral in place of Swartzite, such as Schoepite or Rutherfordine if no data are available. However, such substitution will render my output a gross approximation. Has anyone determined or located reliable kinetic rate constants for Swartzite while modeling uranium mineral saturation? Has anyone been unable to find kinetic rate constants for a mineral, and ended up substituting in a similar mineral? Any help would be useful. Thanks. GWB_U_02172012.dat