A study of wet chemistry determinations of iron cations in biotite

Abstract

Content of iron cations in three biotite specimens of true trioctahedral mica were determined by Mössbauer spectroscopy, electron microprobe and wet-chemistry methods. International certified reference materials were analyzed simultaneously with micas to evaluate the accuracy of the wet-chemistry method. High precision Mössbauer spectroscopic Fe3+/Fe2+ ratios coupled with the electron microprobe iron determinations were compared with the wet-chemical data. Comparisons of data show that in wet-chemistry method powdered micas dissolve more readily during acid attack than the granular micas and thus yield higher precision and accuracy.

Keywords


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