[en] Two strontium-90 beta sources was independently calibrated with known cobalt-60 gamma doses using commercially obtainable chemically pure quartz as TL-phosphor, which was prepared in the same manner as in the quartz inclusion technique. Direct comparison of two beta sources yielded results in good agreement with the primary calibrations. It is concluded that quartz could serve as a cheap phosphor for a wide interlaboratory program to compare beta sources. (author)