A Mössbauer spectroscopy study of the intermetallics RE 6 Fe 14−t M t , where RENd or Pr, MGa or Al and x=1 or 2 was undertaken. A comparative analysis of the Mössbauer spectra showed that the second Al or Ga atom substitutes preferentially for the Fe atoms located at the 161 sites. The reduction of the hyperfine fields in Nd 6 Fe 12 M 2 , as compared With Nd 6 Fe 13 M. mainly at the 16k, 161 1 and 161 2 and the corresponding decrease of the average Fe moment gives rise to a total magnetic moment of 41μ B per formula unit in excellent agreement with previous saturation magnetisation measurements.