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This chapter focuses on diffusion in non-silicate minerals that do not fall under any of the other chapter categories. This includes minerals that are not oxides (fluorite, sulfide minerals, diamond) and those, like the carbonates, that are not among the oxide minerals discussed in Chapter 17 of this volume (Van Orman and Crispin 2010). Although there are numerous minerals in these categories, limited diffusion data exist for many of them, so the primary phases that will be considered are carbonates, fluorite, diamond, and sulfide minerals.
Carbonate minerals are major constituents of sediments and many sedimentary rocks. Fractionation of O and C isotopes between carbonate rocks and fluids can provide insight into paleoclimates and sedimentary histories; the behavior of the isotopes of major elements in calcite and aragonite has become of increasing interest due to the important role of CO2 and carbonate dissolution/precipitation in the oceans and the connections to global climate (e.g., Arita and Wada 1990; Chacko et al. 1991; Dickson 1991; Beck et al. 1992; Cole 1992; Graham et al 1998; Cole and Chakraborty 2001). Ca-Mg diffusion rates affect the process of dolomitization (Hardie 1987; Fisler and Cygan 1999), and characterization of diffusion of these species is important for refinements in application of the calcite-dolomite geothermometer (e.g., Essene 1982; Farver and Yund 1996) and better understanding of deformation mechanisms. For example, calcium isotopic fractionation between seawater and calcite and aragonite has been observed in marine samples (Zhu and MacDougall 1998; de la Rocha and DePaolo 2000; Schmitt et al. 2003) with possible applications as a thermometer. Ca isotopic fractionation also occurs in biologic systems, as in the growth of foraminifera (Skulan et al. 1997; Zhu and Macdougall 1998). Diffusion of major elemental species plays an important rate-limiting …