Fig. 14.-Primary muscovite (Ms) and co-orientation metasomatic muscovite (Ms single prime)

Left figure, plane-polarized light. Right figure, crossed polars. The clear and transparent muscovite (Ms) epitaxially growing on a primary idiomorphic biotite (Bi) is primary, while the mottled muscovite (Ms single prime) containing the Fe-analyte has a co-orientation replacement origin from biotite. Huichang granite, Jiangxi Province.