An analytical method has been developed for the determination of Se, Br, Sr, Ag, Cd and In in some mixtures applying (γ, γ′)-type
reactions. This method provides a high degree of selectivity and precision if the concentration of the element in the sample
is a few per cent or more. Using an 80-kCi60Co gamma-radiation source, as low as 0.002–0.14% impurities could be determined in 50-g samples; this corresponds to 1–70
mg quantities of the particular elements.