Seeing that almost all properties of the portland cement can be attributed to some forms of linear combinations of proper functions pertaining to the mineral components in the clinker, we have to appreciate still the facilities of the recasting method. Although there have already been a number of proposals as to the recasting, we do not know yet any satisfactory procedure, however.According to the opinion of one of the authors, attentions should be paid to the diadochic phenomena, which are universally recognized among the mineral worlds including the socalled artificial minerals, along with the proper recasting operations.In the first place, we provided for the rudimentary data indispensable for the determination of n-value in the general formula C6AnF3-n for the iron containing phase in the clinker, by means of the X-ray diffractograms. Conveniently enough we found that the d-values of some suitable hkl vary almost linearly with the n-values, as shown in Figs. 21-25, excepting those parts near n=2.In the second place, we called our attention to the diadochic transfers of a few percentages of silicon into the alminum containing phases to realize the inversion in the proportion of the contents between C3S and C2S, which has long been the nuissance of the conventional recasting procedures as formerly pointed out by one of the present authors as well as by Eitel, Bogue and others.With the incorporation of such considerations on the diadochy in general sense along with the proper recasting procedures as shown in Tab. 5, we could get results which were really competetive with those by the laborious and tendious microscopic mineral estimations as shown by the examples in the following texts.The results of the present studies were already presented at the June Meeting (Tokyo, 1960) of the Japanese Ceramic Association.