Contributions to Mineralogy and Petrology

, Volume 42, Issue 1, pp 33–42 | Cite as

Compositional variation of muscovite as a function of metamorphic grade and assemblage in metapelites from N.W. Maine

  • C. V. Guidotti


Chemical data are presented for 49 muscovites from high and low Al specimens collected form N.W. Maine at metamorphic grades ranging from the upper staurolite to the upper sillimanite zone. Data also are presented for two muscovite from St. Paul Island, two muscovites+three paragonites from Gassetts, Vermont, and one muscovite from an adamellite in N. W. Maine.

These data given further information on the effects of P, T, and bulk composition on muscovite composition. Specifically, temperature clearly influences the Na/Na+K ratio of muscovite in limiting assemblages but may not have much effect on the phengite content. Increase in pressure clearly does cause an increase in phengite content. Bulk composition (assemblage) has a very great effect on both Na/Na+K ratio and phengite content so that attempts to use either of these factors to monitor metamorphic grade should generally be done in the context of a limiting assemblage.


Mineral Resource Compositional Variation Chemical Data Bulk Composition Sillimanite 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1973

Authors and Affiliations

  • C. V. Guidotti
    • 1
  1. 1.Department of Geology and GeophysicsUniversity of WisconsinMadison

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