02 



GREEN MOINTAINS IN .M ASS AC 11 ("SETTS. 



micas of the groundmass bend around the albites in gentle curves (see PI. vm, 

 b), and often a band of mica cuts across a feldspar. The albite contains 

 inclusions of muscovite, biotite, chlorite, quartz, magnetite, rutile, etc., 

 according to their presence or absence in the rock. It is common to see 

 them in curving bands parallel to the banding of the same minerals outside 

 the feldspar. These feldspars evidently crystallized contemporaneously 

 with the other minerals in the rock. 



W 



Fig. 2:1.— Ml.it. schist (Hoosa. schist). Damp, Central shaft. About one-eighth natural size. 



Here the quartz lenses are again prominent. It is round that they are always parallel to the stratiticatii 



The quartz occurs in little grains often arranged in stringers. The mus- 

 covite is either in stout plates or is a mass of interlacing fibers or plates — 

 the structure characteristic of sericite. Biotite and chlorite occur in plates 

 or irregular scales; the two minerals occur sometimes side by side in the 

 same piece without any sharp boundary between the two, so that the 



