Abstract
The standard co57 -Cu source was provided with a 14.4 Kev monoenergetic γ - ray radiation. Using this source ue performed a systematic investigation of the Mossbauer absorption line spectra of several kinds of clay mineralrs containing various iron compounds. Their isomer shifts and alectric quadrupole splittings were also observed. For comparison with the Mossbauer effect of Fe57, the source of Dy161 and its related absorbers were studied. Meanwhile, different circuitries for the equipment set - up with the mode of interest were also studied.