GRAPHITE   IN   MAINE. 
By  George  Otis  Smith. 
Two  occurrences  of  graphite  in  western  Maine  were  visited  by  the  writer  in  1905.  At 
one  locality,  near  Madrid,  Franklin  County,  development  work  had  been  prosecuted 
throughout  the  summer  by  the  Maine  Graphite  Company,  so  that  the  relationships  of  the 
deposit  were  well  exhibited.  The  other  locality  is  in  Yarmouth,  Cumberland  County,  and 
although  no  recent  work  has  been  done  here  the  exposures  are  sufficient  to  indicate  the 
character  of  the  deposit.  These  two  occurrences  are  of  interest  from  both  the  industrial 
and  the  scientific  standpoint.  The  evidence  presented  in  the  following  descriptions  has  a 
scientific  value  as  indicating  two  modes  of  origin  of  graphite,  but  these  genetic  relation- 
ships have  in  turn  a  direct  and  important  bearing  on  the  question  of  economic  value. 
MADRID    OCCURRENCE. 
The  Madrid  graphite  deposit  is  located  in  the  town  of  Phillips,  although  only  a  short 
distance  from  the  little  village  of  Madrid.  The  nearest  railroad  point  is  Madrid  station,  on 
the  Phillips  and  Rangeley  Railroad.  The  schist,  which  together  with  intrusive  granite 
constitutes  the  country  rock  in  this  region,  outcrops  here  along  the  northern  slope  of  a  hill 
immediately  south  of  the  village.  Beds  of  varying  composition  can  be  distinguished  in 
this  schist  and  indicate  a  northeast-southwest  strike.  The  general  dip  is  nearly  vertical, 
although  the  schist  is  much  contorted.  The  development  work  is  in  the  form  of  an  open 
cut  which  extends  into  the  hill  approximately  parallel  with  the  strike  of  the  schist,  the  face 
at  the  southwest  end  measuring  about  30  feel  in  length  by  25  feet  in  height. 
In  the  upper  pari  of  the  lace  on  the  western  side  there  is  a  triangular  area  of  fine-grained 
white  rock  with  a  sandy  texture.  This  rock  contains  varying  amounts  of  quartz  and, 
where  it  cuts  directly  across  the  schist,  shows  a  selvage  of  muscovite  and  a  general  banding 
conformable  with  the  contact  with  the  schisi.  Another  mass  of  similar  rock,  somewhat 
coarser  grained,  occurs  in  the  eastern  part  of  the  same  face,  the  two  being  separated  at  one 
point  by  not  over  2  feet  of  schist.  Near  the  entrance  to  the  cut  and  on  the  east  side  is 
another  mass  of  white  rock  which  probably  connects  with  the  second.  This  third  mass  is 
plainly  pegmatitic  in  texture  ami  composition,  containing  quartz  and  muscovite,  with 
subordinate  amounts  of  feldspar.  Close  examination  of  the  other  masses  of  white  rock, 
especially  where  exposed  on  the  hill  slope  above  the  open  cut,  makes  it  evident  that  these 
are  also  of  pegmatite.  The  three  somewhat  irregular-shaped  masses  may  be  regarded  as 
possibly  portions  of  one  intrusive  body  of  pegmatite,  which  in  part  cuts  across  the  schist 
and  in  part  follows  the  bedding  planes. 
The  graphite  occurs  locally  in  the  schist ,  always  close  to  the  contact  with  the  white  rock, 
with  the  exception  of  the  sporadic  occurrence  of  a  few  slickensided  lenses  of  graphitic  rock, 
about  18  inches  in  their  longer  diameters.  At  no  place  seen  in  this  rock  cut  did  the  graphitic 
portion  of  the  schist  extend  more  than  a  few  inches  from  the  contact.  At  the  point  in  the 
face  of  the  cut  where  the  two  bodies  of  pegmatite  are  nearest  together  the  schist  is  crumpled 
and  crushed  into  blocks  which  appear  to  be  largely  graphite.  However,  all  of  the  schist 
is  not  strongly  graphitic  at  the  pegmatite  contact.  Where  the  bedding  planes  can  be 
traced  with  certainty,  it  is  seen  that  one  stratum  may  be  graphitic  and  the  beds  on  either 
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