﻿Judd 
  and 
  Hidden 
  — 
  Ritby 
  in 
  North 
  Carolina. 
  379 
  

  

  of 
  Korth 
  Carolina; 
  and, 
  in 
  either 
  case, 
  corundum 
  may 
  have 
  

   been 
  formed 
  by 
  the 
  separation 
  of 
  dissolved 
  alumina. 
  The 
  

   great 
  promise 
  which 
  is 
  held 
  out 
  by 
  the 
  fine 
  color 
  and 
  quality 
  

   of 
  many 
  of 
  the 
  ruby 
  crystals 
  from 
  this 
  new 
  locality 
  would 
  

   seem 
  to 
  warrant 
  a 
  continuance 
  of 
  the 
  prospecting 
  work 
  lately 
  

   inaugurated 
  there, 
  and 
  it 
  is 
  to 
  be 
  hoped 
  that 
  the 
  interesting 
  

   problem 
  of 
  the 
  true 
  origin 
  of 
  these 
  rubies 
  may 
  be 
  definitely 
  

   settled 
  when 
  the 
  explorations 
  on 
  Co 
  wee- 
  Creek 
  shall 
  have 
  fur- 
  

   nished 
  fuller 
  data 
  and 
  more 
  conclusive 
  evidence 
  concerning 
  the 
  

   primary 
  condition 
  of 
  the 
  associated 
  minerals 
  and 
  the 
  nature 
  

   and 
  relations 
  of 
  the 
  rocks 
  of 
  the 
  district. 
  

  

  On 
  the 
  Crystallography 
  of 
  the 
  Rubies 
  from 
  Macon 
  County^ 
  

   North 
  Carolina 
  ; 
  by 
  J. 
  H. 
  Pratt. 
  

  

  The 
  ruby 
  crystals 
  from 
  the 
  Cowee 
  Yalley, 
  Macon 
  County, 
  

   ^orth 
  Carolina, 
  show 
  a 
  very 
  wide 
  variation 
  in 
  their 
  develop- 
  

   ment. 
  Although 
  many 
  of 
  the 
  crystals 
  are 
  so 
  striated 
  that 
  no 
  

   crystallographic 
  measurements 
  were 
  possible 
  on 
  the 
  reflecting 
  

   goniometer, 
  the 
  faces 
  were 
  readily 
  identified 
  by 
  means 
  of 
  the 
  

   contact 
  goniometer. 
  On 
  some 
  of 
  the 
  crystals 
  the 
  faces 
  were 
  

   bright 
  and 
  smooth, 
  making 
  them 
  well 
  adapted 
  for 
  measure- 
  

   ment 
  on 
  the 
  reflecting 
  goniometer. 
  The 
  following 
  references 
  

   are 
  to 
  the 
  figures 
  on 
  p. 
  380. 
  

  

  Among 
  the 
  crystals 
  examined 
  there 
  were 
  two 
  common 
  

   habits 
  noticed, 
  one, 
  as 
  shown 
  in 
  figs. 
  1 
  and 
  2, 
  which 
  is 
  a 
  com- 
  

   bination 
  of 
  the 
  base 
  c(OOOl) 
  and 
  the 
  unit 
  rhombohedron 
  (lOlj.); 
  

   the 
  other, 
  represented 
  by 
  tigs. 
  3 
  to 
  6, 
  where 
  the 
  prism 
  6^(1120) 
  

   is 
  very 
  prominently 
  developed. 
  The 
  rhombohedral 
  crystals 
  

   vary 
  from 
  those 
  where 
  the 
  base 
  is 
  largely 
  developed, 
  having 
  a 
  

   diameter 
  of 
  12"'"', 
  while 
  the 
  rhombohedron 
  is 
  only 
  1*5°'% 
  to 
  

   some 
  (fig. 
  1) 
  which 
  have 
  the 
  base 
  and 
  rhombohedron 
  more 
  

   equally 
  developed. 
  The 
  majority 
  of 
  these 
  crystals 
  have, 
  how- 
  

   ever, 
  the 
  base 
  more 
  largely 
  developed, 
  thus 
  giving 
  the 
  crystals 
  

   a 
  flat 
  tabular 
  appearance. 
  This 
  rhombohedral 
  develo23ment 
  is 
  

   ver}^ 
  similar 
  to 
  that 
  of 
  the 
  sapphires 
  from 
  Togo 
  Gulch, 
  Mon- 
  

   tana, 
  described 
  by 
  the 
  author."^ 
  

  

  On 
  some 
  of 
  the 
  prismatic 
  crystals 
  the 
  prism 
  reaches 
  a 
  length 
  

   of 
  nearly 
  15"'"^ 
  in 
  the 
  direction 
  of 
  the 
  c-axis, 
  and 
  has 
  the 
  rhom- 
  

   bohedron 
  but 
  slightly 
  developed 
  (fig. 
  3), 
  while 
  on 
  others 
  the 
  

   prism 
  is 
  very 
  short 
  and 
  the 
  rhombohedron 
  sometimes 
  is 
  want- 
  

   ing, 
  as 
  represented 
  in 
  figs. 
  4 
  and 
  5. 
  

  

  Another 
  habit 
  of 
  these 
  crystals 
  is 
  shown 
  in 
  figs. 
  7 
  and 
  8. 
  

   There 
  the 
  pyramid 
  ?i(2243) 
  is 
  well 
  developed. 
  This 
  face 
  was 
  

   identified 
  by 
  means 
  of 
  the 
  contact 
  goniometer, 
  the 
  measure- 
  

   ments 
  approximating 
  closely 
  to 
  the 
  calculated 
  angles. 
  The 
  

  

  * 
  This 
  Journal, 
  vol. 
  iv, 
  1897, 
  p. 
  424. 
  

  

  