Measurements were made of Ti diffusion in quartz under dry 1atm conditions. The experiments were performed by using synthetic and natural quartz and a TiO2 powder source, with the Ti profiles being obtained by Rutherford back-scattering spectrometry. At 700 to 1150C, an Arrhenius relationship was found for diffusion parallel to (001):

D (m2/s) = 7 x 10-8 exp[-273(kJ/mol)/RT]

Similar diffusivities were obtained for both synthetic and natural quartz, and for a range of Ti source materials, including natural titanite powder and rutile–quartz single crystal diffusion couples. Although Ti diffusion appeared to be slightly slower in the direction normal to c, this difference was not great.

Ti Diffusion in Quartz. D.J.Cherniak, E.B.Watson, D.A.Wark: Chemical Geology, 2007, 236[1-2], 65-74