Adularia

1 definition found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Adularia \Ad`u*la"ri*a\, n. [From Adula, a mountain peak in
     Switzerland, where fine specimens are found.] (Min.)
     A transparent or translucent variety of common feldspar, or
     orthoclase, which often shows pearly opalescent reflections;
     -- called by lapidaries moonstone.
     [1913 Webster]