The trapping of helium in cristobalite was studied at 293 to 857K. The diffusion coefficients could be represented by an Arrhenius equation:

D(cm2/s) = 2.0 x 10-2exp[-13800/RT]

at 244 to 335K.

R.M.Barrer, D.E.W.Vaughan: Transactions of the Faraday Society, 1967, 63, 2275-90