424  CONTRIBUTIONS    TO    ECONOMIC1    GEOLOGY,  1900,  PAKT    T. 
locally  muscovite  in  particular  occurs  in  bunches  of  books.     Liquids 
and  gases  originating  from  the  pegmatitic  magma  have  considerably  I 
metamorphosed  bands  of  schist  on  either  side  of  the  pegmatite  dikes. 
DESCRIPTION   OF   PROSPECTS. 
The  principal  mica  prospects  of  the  Hartville  uplift  are  the  Crystal 
Palace,  the  Savage,  the  New  York,  and  the  Minnie. 
The  Crystal  Palace  claim,  owned  by  Lauck  &  Stein,  is  situated  on  t  he 
south  side  of  a  steep  valley  in  the  center  of  theNE.J  sec.34,  T.  28  N.,  I 
R.65W.    An  open  cut  60  feel  long  has  been  made  on  a  pegmatite  dike  6    I 
feet  wide  at  its  floor  and  15  to  IS  feet  wide  at  its  top.     At  the  southwest 
end  of  the  cut  the  pegmatite  is  covered  by  talus,  but  it  is  exposed  for  a  I 
longdistance  along  its  strike,  w  hichisN.  60°  E.     It  is  acoarsely  crystal-  1 
line  aggregate  of  feldspar,  white  quartz,  muscovite,  tourmaline,  brown  ] 
garnet,  and  a  little  beryl.     The  black  tourmaline  is  not  prominent  and  I 
is  largely  confined  to  the  edges.      Quartz  was  the  last  mineral  of  the 
pegmatite  to  solidify  and  a  portion  of  it  was  still  held  in  solution  by 
the  magmatic  waters  after  the  pegmatite  had  consolidated,  since  it  I 
also  occurs  in  indistinct  veins  which  cut  the  pegmatite.     The  distri- 
bution of  the  muscovite  is  bunchy  and  in  consequence  an  estimation 
of  the  amount  of  muscovite  in  the  walls  of  the  open  cut   is  difficult, 
although  it   probably  forms  from   10  to  15  per  cent  of  the  pegmatite. 
The  muscovite  tends  to  form  hexagonal   plates,  some  of  which  are  2    I 
IVct  across  and  3  or  4  inches  thick.     It  is  a  good-grade  "  water"  mica,  I 
although  rulings  are  common    and  in  some  of  it  plates  of  feldspar-  and 
quartz   lie    between    the    mica    leaves.      To    the    northeast    across    the 
gulch  the  pegmatite  contains  a  greater  proportion  of  tourmaline  and 
beryl,   and    though    muscovite    is   equally   abundant,    the    plates   are 
much  smaller.      At  present  there  are  2  or  3  tons  of  mica  on  the  dump. 
Some  of  this  is  high-grade  material  which  could  he  used  for  sheets. 
The  Savage  claim,  also  the  property  of  Lauck  cv.  Stein,  is  situated 
near  the  center  of  the  S.  i  sec.  26,  T.  28  X.,  R.  65  W.  An  open  cut 
is  here  located  on  a  pegmatite  dike4  10  feel  wide,  which  courses  N.  65° 
E.  About  200  feet  farther  southwest  the  dike  either  pinches  out  or 
plunges  beneath  the  surface,  and  to  the  northeast  it  becomes  nar- 
rower and  the  muscovite  plates  become  smaller.  The  composition 
of  this  pegmatite  is  similar  to  that  at  the  Crystal  Palace  claim, 
although  bluish-green  beryl  is  more  abundant.  In  many  places  thin 
distorted  crystals  of  tourmaline  lie  between  the  muscovite  leaves. 
Muscovite  in  plates,  some  of  them  12  inches  in  diameter,  forms  10  to 
15  per  cent  of  the  pegmatite.  From  this  prospect  sheets  of  mica  1 1 
by  13  inches  and  free  from  flaws  have  been  obtained. 
The  New  York  claim  is  situated  in  the  northeast  corner  of  sec.  35, 
T.  28  N.;  R.  65  W.,  and  is  owned  by  Mr.  Frederick.  At  the  open  cut 
the  pegmatite  dike  is  from  6  to  10  feet  wide;  it  narrows  to  5  feet  350 
