“…The role of fluids in pseudomorphic reactions has traditionally been greatly underestimated, and replacement reactions have mainly been considered in terms of diffusiondriven movement of cations within a solid (e.g., Thornber, 1975a;Cole, 1983;Wilkin and Barnes, 1996;Cole and Chakraborty, 2001;Eda et al, 2004Eda et al, , 2006Hunger and Benning, 2007). This mechanism involves the preservation of the anionic structural framework, while cations appear to freely interchange through larger atomic sites or interconnected channels within the structure (Harland, 1994).…”