It is usual in Mössbauer spectroscopy analysis to take the subspectra areas as a measure of the concentration of the Fe compounds that generate them. In soils, the presence of different-size particles of different nature makes the semiquantitative Mössbauer studies difficult, and some handling of the sample must be carried out in order to get reliable area results (Bowman et al. 1967; Muir 1968; Williamson et al. 1981).