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  Judd 
  and 
  Hidden 
  — 
  Ruhy 
  in 
  North 
  Carolina. 
  

  

  The 
  association 
  of 
  rubies 
  and 
  rhodolite 
  in 
  this 
  district 
  is 
  not 
  

   onlj 
  proved 
  by 
  their 
  constant 
  occurrence 
  together 
  in 
  the 
  sapro- 
  

   litic 
  material 
  and 
  in 
  the 
  gravels, 
  but 
  we 
  fonnd 
  indisputable 
  

   evidence 
  that 
  the 
  garnets 
  have 
  crystallized 
  first 
  and 
  that 
  the 
  

   corundum 
  has 
  solidified 
  afterwards 
  and 
  has 
  enclosed 
  the 
  garnets 
  

   partially 
  or 
  entirely 
  in 
  its 
  crystals. 
  Some 
  of 
  the 
  ruby 
  crystals 
  

   l3ear 
  impressions, 
  of 
  wliich 
  a 
  mould 
  can 
  be 
  taken 
  in 
  wax, 
  and 
  

   these 
  impressions 
  give 
  with 
  a 
  goniometer 
  the 
  angles 
  of 
  the 
  

   rhombic-dodecahedron 
  or 
  the 
  trapezohedron. 
  In 
  some 
  cases 
  

   clear 
  crystals 
  of 
  ruby 
  corundum 
  have 
  been 
  broken 
  open, 
  and 
  

   minute 
  garnets 
  actually 
  taken 
  out 
  of 
  the 
  middle 
  of 
  them. 
  In 
  

   other 
  cases 
  fractured 
  surfaces 
  of 
  the 
  basic 
  rocks 
  show 
  corun- 
  

   dum 
  surrounding 
  and 
  enclosing 
  garnet 
  crystals, 
  while 
  in 
  other 
  

   cases 
  cut 
  gems 
  of 
  ruby 
  can 
  be 
  seen 
  to 
  have 
  in 
  their 
  midst 
  a 
  

   garnet 
  crystal. 
  

  

  So 
  far 
  as 
  our 
  experience 
  goes, 
  this 
  enclosure 
  of 
  garnet 
  by 
  

   corundum 
  is 
  peculiar 
  to 
  this 
  special 
  Cowee 
  district, 
  and 
  serves 
  

   to 
  distinguish 
  the 
  corundum 
  found 
  in 
  it 
  from 
  that 
  occurring 
  in 
  

   any 
  of 
  the 
  tracts 
  where 
  the 
  mineral 
  occurs 
  in 
  peridotites 
  

   (dunite, 
  etc.), 
  or 
  at 
  the 
  junction 
  of 
  peridotites 
  with 
  the 
  crystal- 
  

   line 
  schists. 
  

  

  This 
  remarkable 
  association 
  of 
  garnet 
  and 
  corundum 
  is 
  well 
  

   illustrated 
  by 
  a 
  drawing 
  (fig. 
  3) 
  made 
  upon 
  the 
  spot 
  by 
  one 
  of 
  

   us 
  from 
  a 
  specimen. 
  

  

  Fig. 
  3. 
  Corundum 
  enclosing 
  Crystals 
  of 
  Garnet. 
  

  

  Specimens 
  are 
  occasionally 
  found 
  in 
  the 
  district 
  which 
  appear 
  

   to 
  be 
  pseudomorphs 
  of 
  quartz 
  after 
  dodecahedral 
  garnets. 
  

  

  Spinel, 
  which 
  is 
  so 
  constantly 
  associated 
  with 
  the 
  corundum 
  

   (ruby) 
  of 
  Burma, 
  is 
  rare 
  in 
  the 
  American 
  locality. 
  The 
  fine 
  

   red 
  spinels, 
  so 
  similar 
  in 
  tint 
  to 
  the 
  rubies 
  themselves, 
  and 
  so 
  

   conspicuous 
  in 
  the 
  Burma 
  localities, 
  appear 
  to 
  be 
  entirely 
  

   wanting 
  in 
  the 
  North 
  Carolina 
  area. 
  Three 
  varieties 
  of 
  spinel, 
  

   namely, 
  picotite, 
  gahnite, 
  and 
  chromite 
  (the 
  last 
  being 
  rare), 
  

   have 
  been 
  found 
  both 
  in 
  the 
  alluvial 
  deposits 
  and 
  in 
  situ 
  in 
  

   the 
  basic 
  rocks. 
  

  

  Of 
  minerals 
  specially 
  characteristic 
  of 
  materials 
  formed 
  by- 
  

   contact 
  metamoyphism, 
  the 
  following 
  have 
  been 
  found 
  : 
  Silli- 
  

   manite 
  (fibrolite), 
  cyanite, 
  staurolite 
  (often 
  very 
  clear 
  and 
  ^^em- 
  

   like 
  in 
  character), 
  and 
  cordierite 
  or 
  iolite 
  (colorless 
  and 
  without 
  

   dichroism). 
  

  

  