Muonium spin relaxation measurements of the alpha-, beta-, and gamma-t
ridymite phases of quartz have been carried out over a temperature ran
ge from 300 to 1250 K. Anomalous relaxation rate increases are observe
d which may result either from resonance coupling between the other im
purity ions and defects in the lattice and the diffusing muonium, or m
ay result from phonon interactions with the muonium quadrupole moment.