Paragonite, also known as Natron-Glimmer, is a mineral, related to muscovite. Its empirical formula is NaAl2[(OH)2|AlSi3O10]. A wide solvus separates muscovite from paragonite, such that there is little solid solution along the vector Na+K+ and apparent micas of intermediate composition is most commonly a microscopic (or even sub-microscopic) inte... Found on http://en.wikipedia.org/wiki/Paragonite
mica mineral similar to muscovite, a basic silicate of sodium and aluminum; a member of the common mica group. It was thought to be an uncommon ... [2 related articles] Found on http://www.britannica.com/eb/a-z/p/16
Pa·rag'o·nite noun [ From Greek ..., present participle of ... to mislead.] (Min.) A kind of mica related to muscovite, but containing soda instead of potash. It is characteristic of the paragonite schist of the Alps. Found on http://www.encyclo.co.uk/webster/P/18