Comparison of ratios (Fe³⁺/(Fe³⁺+Fe²⁺)) in biotite between powdered and oriented samples by Mössbauer spectroscopy

Abstract

Ferrous iron in biotite can be transformed into ferric iron as weathering. Ratios of ferric iron in biotite can be quantitatively measured by Mössbauer spectroscopy. Natural biotite was annealed in air under 6 different conditions, and, biotite samples of various ferric iron ratios were prepared. We measured Mössbauer spectrums of oriented biotite and powdered biotite and compared ferric iron ratios between them.