Diffusion coefficients for Sr in fluorapatite at 900 to 1250C were obtained by measuring diffusional uptake profiles of the element in the margins of gem-quality crystals. The crystals were immersed in synthetic melts enriched in the trace element and presaturated in apatite. The resulting diffusion gradients were characterized by electron microprobe analysis. The diffusivities were described by:

D(cm2/s) = 412 exp[-100000/RT]

E.B.Watson, T.M.Harrison, F.J.Ryerson: Geochimica et Cosmochimica Acta, 1985, 49[8], 1813-23