Transformation of mica to high-charge smectite, depending on the particle size, in a yellow-brown soil of China.

TLDR: In this paper, the authors examined the mineralogical composition of a Yellow-brown soil of China and found that micas and their transformation products dominated the clay fraction, however, the transformation products of micas were different between the fine and coarse (0.2-2 μm) clay fractions.

Abstract: Clay mineralogical composition of a Yellow-brown soil of China was examined. Common to the A and C horizons, micas and their transformation products dominated the clay fraction. The transformation products of micas were, however, different between the fine (<0.2 μm) and coarse (0.2-2 μm) clay fractions. Irregularly interstratified mica/smectite or mica/vermiculite/smectite of the smectite-rich phase was found in the fine clay fraction, while smectite and regularly interstratified mica/smectite were detected in the coarse clay fraction. The endo-type and exo-type K-replacement models were proposed to explain the different transformation products between the two clay fractions