%P 91-99 %C Szeged %O Bibliogr.: p. 98-99. ; ill. ; ĂśsszefoglalĂĄs angol nyelven %T Characterization of kaolin minerals of different origin : (essentially from Hungarian deposits) %J Acta mineralogica-petrographica %A KocsĂĄrdy Ăva %A Heydemann Annerose %D 1980 %I University of Szeged, Department of Mineralogy, Geochemistry and Petrology %L acta24676 %K KĹzettan, ĂsvĂĄnytan, FĂśldtan %V 24 %X Kaolinite minerals from weathered rhyolite tuff's, from sedimentary kaolin clays, bauxites and argillaceous lignites were studied by X-ray diffractographic, infrared-spectroscopic and thermoanalytic methods. In addition to determining the mineralogical composition and the grain size distribution of bulk samples, the authors obtained closer characterization of various kaolinite minerals by measuring the polytypes and the crystallinity state of the minerals. X-ray diffractography was used for assessing the Hinkley index and the half-width of the 001-reflection, while infrared techniques were resorted to for assessing, among other things, the Kt-index (Kt = E3M5 cm ~ ' / E3620 cm- 1 ) and the K2-index (K2=E3670+E365 0 + E3620/E3695). All these results should be relied on for attempting to distinguish between kaolinites of different genesis.