Potash feldspar, muscovite, and quartz are crystallized.
The I-type has strontium-87/strontium-86 strontium-87/strontium-86 strontium-87/strontium-86anite, and allanite but no muscovite.
The overall range is from 2.76 for muscovite to 3.2 for iron-rich biotite.
Chlorite, muscovite, staurolite, and chloritoid may also occur.
It seems probable that much paragonite has been mistaken for muscovite.
The reaction curves for Al2SiO5 and for muscovite + quartz ←→ potassium-feldspar + sillimanite + H2O are significant in metamorphic rocks that have a high aluminum oxide (Al2O3) content as compared to other components (e.g., calcium oxide [CaO], magnesium oxide [MgO], and ferrous oxide [FeO]).
During the Muscovite period (c. 14th 17th centuries), the Slavic and Byzantine cultural substrates were enriched and modified by Asiatic influences carried by the Mongol hordes.
Single crystals of spodumene exceeding 13 metres (43 feet) in length were mined for their lithium content in the Black Hills of South Dakota, U.S. Spodumene is typically associated with microcline, albite, quartz, muscovite, lepidolite, beryl, and tourmaline.
If neither feldspar is in great excess, neither amphibole nor pyroxene is likely to be an essential constituent; the other minerals will then ordinarily be either biotite or muscovite, or both.
Both types of granitoids may also contain biotite and muscovite.
The majority of clay-size micas are dioctahedral aluminous species; those similar to muscovite are called illite and generally occur in sediments.
