Perthitic

1 definition found

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

  Perthite \Perth"ite\, n. [So called from Perth, in canada.]
     (Min.)
     A kind of feldspar consisting of a laminated intertexture of
     albite and orthoclase, usually of different colors. --
     {Per*thit"ic}, a.
     [1913 Webster]