GRANITES OF NORTH CAROLINA 



399 



schistose structure are shown. Not in the same mass, however; for 

 not in a single instance has such been observed. Whether the entirely 

 schistose structure is more or less sharply and completely separated 

 from the massive, or whether they grade from one into the other, it 

 is impossible to say, owing largely to the lack of sufficient exposures 

 of the rocks. Even in most of those granites which megascopically 



Fig. 4. — Vertical jointing in granite. City of Charlotte quarry, North Carolina. 



appear massive, more or less evidence is shown in the thin sections 

 of the effects of dynamic forces, in peripheral shattering or granula- 

 tion, and in strained shadows and fractures in the quartz and the 

 feldspar. In such cases no semblance of rearrangement of the min- 

 eral components along certain definite lines appears. 



Basic inclusions. — The granite in many of the quarries contains 

 inclusions of basic segregations which were formed from the cooling 

 magma. These are invariably of darker color and finer grain than 

 the inclosing granite, and are entirely massive. Sections from them 

 resemble closely the inclosing granites in mineral composition, except 



