﻿378 
  Judd 
  and 
  Hidden 
  — 
  Buhy 
  in 
  JSorth 
  Carolina. 
  

  

  it 
  may 
  at 
  first 
  sight 
  appear 
  that 
  it 
  is 
  impossible 
  to 
  ascribe 
  an 
  

   igneous 
  origin 
  to 
  corundum 
  enclosing 
  a 
  mineral 
  with 
  so 
  much 
  

   lower 
  a 
  fusing 
  point 
  as 
  that 
  of 
  garnet. 
  

  

  A 
  little 
  consideration 
  will, 
  however, 
  show 
  that 
  this 
  objection 
  

   has 
  little 
  validity. 
  The 
  temperature 
  at 
  which 
  alumina 
  is 
  dis- 
  

   solved 
  in 
  a 
  mixture 
  of 
  silicates 
  has 
  no 
  necessary 
  connection 
  

   with 
  the 
  fusing 
  point 
  of 
  alumina 
  itself. 
  That 
  the 
  magma 
  from 
  

   which 
  these 
  basic 
  rocks 
  consolidated 
  was 
  fluid 
  at 
  a 
  temperature 
  

   lower 
  than 
  the 
  fusing 
  point 
  of 
  the 
  garnets, 
  or 
  at 
  all 
  events 
  

   that 
  the 
  rock 
  was 
  in 
  a 
  state 
  of 
  aqiieo-igneous 
  fusion 
  at 
  a 
  lower 
  

   temperature, 
  is 
  evidenced 
  by 
  the 
  condition 
  of 
  the 
  beautifully 
  

   crystallized 
  garnets 
  scattered 
  through 
  the 
  basic 
  rocks. 
  At 
  such 
  

   temperatures, 
  according 
  to 
  the 
  experiments 
  of 
  Morozewicz, 
  

   alumina 
  may 
  be 
  largely 
  dissolved 
  in 
  the 
  basic 
  fluid 
  magma, 
  

   and 
  may 
  slowly 
  crystallize 
  out 
  from 
  it. 
  In 
  this 
  way 
  we 
  may 
  

   conceive 
  of 
  the 
  garnets 
  being 
  enclosed 
  in 
  a 
  later 
  formed 
  

   corundum. 
  

  

  There 
  are 
  many 
  points 
  of 
  resemblance 
  between 
  the 
  associa- 
  

   tion 
  of 
  minerals 
  and 
  the 
  forms 
  of 
  crystallization 
  of 
  the 
  Cowee 
  

   Creek 
  rubies 
  and 
  those 
  of 
  Burma. 
  This 
  will 
  become 
  apparent 
  

   if 
  we 
  compare 
  the 
  figures 
  now 
  published 
  with 
  those 
  given 
  by 
  

   Prof. 
  Max 
  Bauer 
  of 
  the 
  Burma 
  rubies."^ 
  

  

  In 
  considering 
  the 
  association 
  of 
  minerals 
  described 
  by 
  Prof. 
  

   Max 
  Bauer 
  in 
  his 
  paper, 
  it 
  should 
  be 
  remembered 
  that 
  the 
  

   material 
  on 
  which 
  that 
  author 
  worked 
  came 
  almost 
  entirely 
  

   from 
  Sagyin, 
  while 
  those 
  described 
  by 
  Mr. 
  Barrington 
  Brown 
  

   and 
  one 
  of 
  us 
  were 
  derived 
  from 
  the 
  Mogok 
  district, 
  nearly 
  60 
  

   miles 
  away. 
  There 
  is 
  reason 
  for 
  concluding 
  that 
  the 
  associa- 
  

   tion 
  of 
  minerals 
  in 
  these 
  two 
  districts 
  of 
  Burma 
  present 
  some 
  

   interesting 
  points 
  of 
  difference. 
  

  

  Although, 
  at 
  first 
  sight, 
  the 
  matrix 
  of 
  the 
  Burma 
  rubies 
  (a 
  

   crystalline 
  lin)estone) 
  may 
  seem 
  so 
  different 
  from 
  that 
  of 
  the 
  

   rubies 
  of 
  Cowee 
  Creek 
  (an 
  amphibolite 
  with 
  garnets, 
  and 
  

   sometimes 
  with 
  a 
  basic 
  feldspar) 
  yet 
  a 
  connection 
  may 
  still 
  be 
  

   shown 
  to 
  exist 
  between 
  the 
  two 
  cases. 
  One 
  of 
  us 
  has 
  brought 
  

   forward 
  evidence 
  to 
  showf 
  that 
  the 
  limestone 
  of 
  Burma 
  has 
  

   been 
  formed 
  by 
  the 
  slow 
  alteration 
  of 
  a 
  lime 
  feldspar. 
  Whether 
  

   the 
  corundum 
  pre-existed 
  in 
  the 
  highly-basic 
  felspathic 
  rock, 
  

   however, 
  or 
  was 
  formed 
  at 
  a 
  later 
  stage, 
  there 
  is 
  no 
  positive 
  

   evidence 
  to 
  show. 
  But 
  the 
  idea 
  of 
  its 
  existence 
  in 
  the 
  silicate 
  

   rock 
  originally 
  is 
  supported 
  by 
  the 
  wonderfully 
  corroded 
  state 
  

   of 
  the 
  corundum 
  crystals. 
  

  

  The 
  magma 
  giving 
  rise 
  to 
  pyroxene 
  gneisses 
  and 
  granulites 
  

   of 
  Burma 
  may 
  not 
  have 
  differed 
  greatly 
  in 
  composition 
  from 
  

   that 
  giving 
  rise 
  to 
  the 
  amphibolites, 
  cclogites, 
  and 
  basic 
  gneiss 
  

  

  *Neues 
  Jahrb. 
  Mio., 
  etc., 
  1896, 
  Bd. 
  ii, 
  Taf. 
  vii. 
  

   fPhil. 
  Trans., 
  toI. 
  clxxxviiA, 
  1896, 
  pp. 
  151-228. 
  

  

  