The temperature - frequency dependences (20-700°C; 0.5-10 kHz) of the dielectric characteristics (ε and tgδ) of natural quartz crystals irradiated with Ƴ-quanta from $^{60}$Со in the dose range 5x10$^5$—2x10$^9$ Rare investigated. It is shown that the maximum loss and the beginning of the rapid increase in ε are shifted due to the irradiation towards higher temperatures, and the shift is greater the higher the radiation dose. It is found that unlike optical properties the radiation change in ε and tgδ does not reach saturation over the whole dose range. A series of successive annealings of the specimens atincreasing temperatures shifts the peak of tg6 and the beginning of the increase in ε in the opposite direction to the temperature, but even annealing at 720°C does not convert the specimen to its initial state. In analyzing the results the applicability of the model of hole Al-centers (used to describe the change in the optical properties due to the action of radiation) to dielectric relaxation processes is discussed.
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