MICA    DEPOSITS    OF    WESTERN    NORTH    CAROLINA. 
411 
The  texture  of  the  pegmatite  is  very  coarsely  granitic.  The  larger 
portion  of  the  mica  is  found  in  the  interior  of  the  pegmatite,  though 
some  occurs  scattered  along  the  walls.  The  quality  is  excellent  and 
the  color  a  beautiful  "rum."  The  yield  in  larger  sizes  is  good,  and 
smaller  sizes  are  plentiful. 
THORN    MOUNTAIN    MINE. 
The  Thorn  Mountain  mine  is  on  the  south  side  of  Thorn  Moun- 
tain, about  3  miles  south  of  Way  ah  Gap,  in  the  Nantahala  Mountains, 
Macon  County.  There  are  two  mines  about  a  quarter  of  a  mile  apart 
on  this  mountain.  The  one  chosen  for  description  is  sometimes 
called  the  No.  2  mine.  The  work  consists  of  a  good-sized  open  cut 
carried  back  about  40  feet  on  the  strike  of  the  pegmatite,  and  about 
7/ 
3 
H-    +    +     + 
+  +    +     +  + 
+   +  +  + 
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•SSZ-. 
Mica  gneissjwall 
rock  and  horses 
Pegmatite  Mica  pockets 
Fig.  14.— Section  across  pegmatite  at  Thorn  Mountain  mine,  Macon,  county,  N.  C. 
Solid  granular 
mica. m  quartz 
25  feet  deep  at  the  farther  end.  The  country  rock  is  pegmatized 
mica  gneiss,  which  strikes  about  N.  50°  E.  and  has  a  high  northwest 
to  vertical  dip.  The  pegmatite  is  from  10  to  15  feet  thick,  and  cuts 
the  gneissic  country  rock  with  a  strike  of  about  N.  25°  E.  and  a  dip 
of  50°  SE.  (See  fig.  14.)  At  least  one  horse  of  mica  gneiss  is  included 
in  it  and  exposed  near  the  bottom  of  the  cut.  This  horse  is  a  large 
one,  with  its  schistosity  turned  at  an  angle  to  that  of  the  wall  rock. 
In  the  face  of  the  cut,  just  below  the  top,  the  pegmatite  either  forks 
or,  more  probably,  includes  another  horse  of  wall  rock.  The  schis- 
tosity of  this  inclusion  is  also  out  of  parallel  with  that  of  the  walls. 
These  horses  are  even  more  highly  pegmatized  than  the  country  rock, 
and  the  lower  one  has  a  very  irregular  outline. 
The  texture  of  the  pegmatite  is  that  of  very  coarse  granite.     The 
mica  does  not  seem  to  be  confined  to  any  one  portion,  but  is  found  in 
