Does muscovite occur as a contact metamorphism mineral, with dacitic intrusion into dacitic rocks?
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$\begingroup$ About your specific question of a dacitic intrusion into dacitic rocks, metadacites can have muscovite. That means the chemistry of dacites as protolyte can develop muscovite. $\endgroup$– user12525Sep 24, 2019 at 18:02
1 Answer
Yes, wikipedia page for muscovite tells:
Muscovite is the most common mica, found in granites, pegmatites, gneisses, and schists, and as a contact metamorphic rock or as a secondary mineral resulting from the alteration of topaz, feldspar, kyanite, etc.
Source: Muscovite, Wikipedia.
As always, you need to corroborate wikipedia is correct, but there are several papers that talk about muscovite on contact metamorphism environments, you can do your own search on a scientifical database.
Here is an example about a paper that deals with muscovite found on contact aureole of Duluth Complex, Minnesota.
So yes it is a mineral phase formed in that conditions of increased temperature due to an intrusion.
For you specific question about contact metadacites, yes too, they can develop muscovite as shown in this book about US geology.