Iron In The Kaolinites From Kaolin And Bauxite Weathering Crusts After Granites: Epr Data

摘要

Kaolinite is an economically important clay mineral. It is proposed to use electron paramagnetic resonance (EPR) in order to estimate the quality of kaolin concentrate while studying deposits. This is related to the fact that most EPR signals of kaolinite are ascribed to Fe~(3+) ions. Some of them occur as an isomor-phic impurity in the mineral structure, while others are incorporated in various micro- and nanoinclusions. The iron admixture significantly affects the physical, chemical, and, of particular importance, technological properties of kaolins. One of the main kaolin sources is weathering crusts, whose formation is accompanied by structural, morphological, and chemical transformations of kaolinite. However, the reasons for its transformation in the weathering profiles of different mineralogical-genetic types and ages remain insufficiently studied.