Belskyy reported in 2005 that allanite-(Ce) from Anadolsk ore mineralization indicates the formation of it in terms of the active continental margin with low oxygen potential. The most allanite samples of granites and pegmatites of the Eastern Azov region (chemical analyses are collected in Table I) resides in the same field on the diagram. Figurative point of allanite from granites and pegmatites of Saltychansk ore occurrence (West part of Azov megablock), Zhytomyr and Tok iv granites located in the field of intracontinental tectonic zone. Obviously, the scattering of points, are caused by uneven content of elements in the various allanite generations which arose due to metamorphic process. That clearly demonstrates two similar analyses from some ore mineralization (points 6 and 7 on the diagram). So Hoshino 's diagram cannot be used to separate of the Ukrainian shield allanite because it has the instability composition. However, even taking into account of the discrepancies in the results caused by different methods and techniques of analysis and samples preparation methods clearly recorded a large quota of Fe'· in the allanites of the Eastern Azov ore occurrences. Apparently, this is a result of the special status of the Azov domain of Earth crust in the Precambrian.
Belskyy used this diagram to check the possibility of its application to allanite of the Ukrainian Shield (Fig. 1). Allanite in the Ukrainian Shield is common accessory mineral in diorite, tonalite, granite pegmatites and granites; moreover, in some granite of Saltychansk complex it is a rock-forming mineral (Tab. I )[Lazarenko et al., 198 I]. In recent years, in the Azov megablock was strike unique ore occurrences of vein-type also known as Anadol allanite "dyke" where allanite content are ranges from 10-80%.
In discriminatory diagram Al10,-Fc10i-rREE10i (Fig. 2), figurative points l and 2 (Anadol ore occurrences, Azov megablock) fall into the opposite fields. He assumed the scattering of points are due to different methods of analysis of the samples. However, in this case, the point would be swapped of places, as convincingly shown for beryl family minerals [Platonov ct al., 2012], where the excessive of Fei• content is due to the "wet" analysis. Consequently, he concluded that the points of scattering are caused by heterogeneous composition of allanite that, in fact, confirmed by electron microscopic analysis [Melnikov et al., 2012] and optically-microscopic observations.
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