The electronic band structures of quartz is altered by the presence of small amounts of impurities such as aluminum, transition metals, alkalies or H2O. Silicon and oxygen selfdiffusion are enhanced by an increase in the concentration of ionized defects such as charged oxygen vacancies or silicon interstitials due to HOH acting as a shallow electronic acceptor. Sodium, by contrast, is a shallow electronic donor and retards the diffusion of these species. To evaluate the effect of the sodium dopant on strength we performed a simple creep experiment (two runs, P=1.5 GPa, T=1073, 1163 ¿K, &sgr;=0.2 to 1 GPa) on Heavitree quartzite (.2 min grain size) containing 350 ppm at. Na. These doped samples deformed 10 times faster than equivalent undoped ones (at the same stress and temperature). Simple diffusion-control of the creep rate is therefore unlikely but an alternative proposed by Hirsch seems consistent with the data. Using Hirsch's model, the weakening could be interpreted as due to an increase in the dislocation glide velocity through an increase of the charged kink population. This implies electronic transfers are strongly influenced by the nature and the abundance of the impurities (including hydroxyls). Sodium could favour the nucleation of negatively charged kinks. Although this is preliminary and was performed using specimens containing grain boundaries and other impurities (A1), we decided to report it rapidly because of its importance to geology; rocks (like quartzites in this example) not only carry water, but also many different impurities which certainly affect their strengths.