Crystallization of nuclear waste disposal glass

The rate of bulk crystallization and shear viscosity eta of a zinc borosilicate simulated nuclear waste disposal glass (SNWDG) were measured above the glass transition temperature T/sub g/. Using recent theories and experimental data for the temperature dependence of eta at <T/sub g/, the crystallization rate below T/sub g/ was calculated; well below T/sub g/ the SNWDG (and, more generally, any high-silica glass) will not crystallize appreciably over any important time period for radioactive decay of fission products