Plate 6 



W. J. Miller, photo 



Upper figure. Photcgraph of a hand specimen of 

 typical Marcy anorthosite. About natural size. Large 

 dark patches are " augen " of labradorite whose natural 

 color is very dark bluish gray. Matrix is mostly granu- 

 lated plagioclase whose natural color is light greenish 

 gray. A few of the small black patches represent 

 chalcopyrite and pyrite whose natural colors are dark 

 and light brass-yellow. 



Lower figure. Photograph of a hand specimen of 

 typical moderately gabbroid and gneissoid Whiteface 

 anorthosite. About natural size, and almost natural 

 color. White material is plagioclase, and dark ma- 

 terial is mostly hornblende and pyroxene. 



