Re: experimental diffusion data for tourmaline
Dave,
I don't know of any experimental diffusion data, but you might want to look
at the following, which might give you a rough idea:

Fortier,S.M. & Giletti,B.J. (1989). An empirical model for predicting diffusion 
coefficients in silicate minerals. Science 245, 1481-1484.

All the best,
Gawen Jenkin

     Dr. Gawen R.T. Jenkin                 e-mail: [log in to unmask]   
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