At present there is a great interest in ultra-high-level dosimetry exceeding the 0.5 MGy which can still be detected more conventionally by the ESR spectroscopy of alanine. Recently, the E1' defect in SiO2 was discovered for dosimetry. The defect generated in crystalline quartz by gamma irradiation was found to be an excellent candidate for ultra-high-level dosimetry at ambient temperatures up to 300 oC. The E1' centre is observed in all pure forms of quartz and silicate, but its dosimetric properties are specific for each material. This provides the precondition for a wide range of applications in dosimetry. Here, the properties of the E1' centre are compared for fused silicates and crystalline quartz. For the first time, supralinearity was observed for the E1' centre and that in silicate glass. The experiments are designed to be used at the HAW project in the Asse salt mine, Braunschweig, FRG.