Sandstones with this component contain authigenic hematite intergrown with kaolinite and illite and replacing muscovite. |
Fine-grained biotite, muscovite and recrystallized quartz grains define the shear foliation. |
This granulite consists of garnet, biotite, muscovite, quartz, plagioclase and cordierite. |
Sericite is fine-grained muscovite formed by alteration of such minerals as feldspar, cordierite, and sillimanite. |
Glauconite is close in composition to muscovite but has some iron, magnesium, sodium, and calcium. |
The matrix is dominantly felsic, but also contains biotite, muscovite, epidote and titanite. |