﻿322 
  G. 
  P. 
  Merrill 
  — 
  Calcium 
  Phosphate 
  in 
  Meteoric 
  Stones. 
  

  

  Art. 
  XXIX. 
  — 
  On 
  the 
  Calcium 
  Phosphate 
  in 
  Meteoric 
  Stones 
  ; 
  

   by 
  George 
  P. 
  Merrill, 
  Head 
  Curator, 
  Department 
  of 
  Geol- 
  

   ogy, 
  United 
  States 
  National 
  Museum. 
  

  

  [Published 
  by 
  permission 
  of 
  the 
  Secretary 
  of 
  the 
  Smithsonian 
  Institution.] 
  

  

  Under 
  the 
  caption 
  On 
  the 
  monticellite-like 
  mineral 
  in 
  mete- 
  

   orites, 
  I 
  have 
  elsewhere* 
  described 
  a 
  previously 
  unrecognized 
  

   form 
  of 
  calcium 
  phosphate 
  occurring 
  among 
  the 
  silicate 
  con- 
  

   stituents 
  of 
  stony 
  meteorites. 
  Examination 
  of 
  a 
  large 
  number 
  

   of 
  thin 
  sections 
  of 
  other 
  stones 
  than 
  those 
  there 
  mentioned 
  has 
  

   shown 
  the 
  occurrence 
  of 
  this 
  mineral 
  to 
  be 
  so 
  widespread 
  as 
  to 
  

   warrant 
  a 
  brief 
  note 
  devoted 
  exclusively 
  to 
  it. 
  

  

  The 
  first 
  noted 
  occurrence 
  of 
  a 
  mineral 
  phosphate 
  in 
  a 
  meteor- 
  

   ite 
  was 
  that 
  of- 
  C. 
  U. 
  Shepard, 
  who 
  in 
  his 
  description 
  of 
  the 
  

   Richmond, 
  Virginia, 
  stone 
  mentions 
  the 
  occurrence 
  of 
  a 
  minute, 
  

   but 
  macroscopically 
  visible, 
  yellow 
  mineral, 
  particles 
  of 
  which 
  

   reacted 
  for 
  phosphorus 
  and 
  calcium 
  and 
  which 
  he 
  interpreted 
  

   as 
  indicative 
  of 
  the 
  mineral 
  apatite. 
  In 
  this 
  he 
  was 
  essentially 
  

   right, 
  but 
  singularly 
  enough 
  the 
  discovery 
  remained 
  unverified 
  

   almost 
  to 
  the 
  present 
  time 
  (see 
  my 
  paper), 
  nor 
  was 
  apatite 
  

   again 
  reported 
  until 
  Berwerthf 
  found 
  it 
  among 
  the 
  silicate 
  con- 
  

   stituents 
  ot 
  the 
  Kodaikanal 
  iron, 
  and 
  TschermakJ 
  in 
  the 
  stone 
  

   of 
  Angra 
  dos 
  Reis. 
  Singularly 
  enough, 
  too, 
  the 
  phosphorus 
  

   reported 
  in 
  chemical 
  analyses 
  of 
  meteorites 
  is 
  in 
  the 
  majority 
  

   of 
  cases 
  relegated 
  to 
  the 
  metallic 
  constituent, 
  a 
  matter 
  to 
  which 
  

   attention 
  was 
  called 
  in 
  my 
  paper 
  on 
  the 
  minor 
  constituents 
  of 
  

   meteorites 
  published 
  by 
  the 
  National 
  Academy 
  of 
  Sciences.§ 
  

   The 
  cause 
  of 
  this 
  is 
  not 
  difficult 
  to 
  determine, 
  as 
  noted 
  in 
  the 
  

   following 
  descriptions, 
  in 
  which 
  I 
  have 
  repeated, 
  in 
  part, 
  mat- 
  

   ter 
  given 
  in 
  previous 
  papers, 
  adding 
  the 
  results 
  of 
  more 
  recent 
  

   observations, 
  particularly 
  in 
  slides 
  of 
  the 
  New 
  Concord 
  and 
  

   Waconda 
  stones. 
  

  

  The 
  New 
  Concord 
  stone, 
  a 
  veined 
  intermediate 
  chondrite 
  

   according 
  to 
  Brezina's 
  classification, 
  fell 
  in 
  1860. 
  It 
  has 
  been 
  

   the 
  subject 
  of 
  much 
  study, 
  and 
  need 
  be 
  referred 
  to 
  here 
  only 
  

   in 
  connection 
  with 
  its 
  mineral 
  and 
  chemical 
  composition. 
  Dr. 
  

   Smith's 
  analyses] 
  showed 
  the 
  stone 
  to 
  consist 
  of 
  10*7 
  per 
  cent 
  

   nickel-iron 
  and 
  89'37 
  per 
  cent 
  " 
  earthy 
  mineral," 
  the 
  nickel- 
  

   iron 
  yielding 
  0*012 
  per 
  cent 
  of 
  phosphorus, 
  but 
  no 
  mention 
  is 
  

   made 
  of 
  this 
  same 
  constituent 
  in 
  the 
  "earthy" 
  portion. 
  An 
  

   examination 
  of 
  the 
  stone 
  in 
  thin 
  sections, 
  a 
  method 
  not 
  avail- 
  

   able 
  in 
  Smith's 
  time, 
  reveals 
  the 
  presence 
  of 
  numerous 
  areas 
  of 
  

   the 
  phosphatic 
  mineral 
  1 
  have 
  elsewhere 
  described 
  and 
  pro- 
  

  

  *Proc. 
  Nat. 
  Acad. 
  Sci., 
  vol. 
  i, 
  p. 
  302, 
  1915. 
  

  

  fMin. 
  Petr. 
  Mitt., 
  vol. 
  xxv, 
  p. 
  188, 
  1906. 
  % 
  Ibid, 
  xxviii, 
  110, 
  1909. 
  

  

  § 
  Memoirs, 
  vol. 
  xiv, 
  p. 
  27, 
  1916. 
  In 
  the 
  42 
  selected 
  analyses 
  there 
  tabu- 
  

   lated, 
  the 
  phosphorus 
  is 
  given 
  as 
  P 
  in 
  24 
  cases 
  and 
  as 
  P 
  2 
  5 
  in 
  the 
  remaining 
  14. 
  

   I 
  This 
  Journal, 
  vol. 
  xxxi, 
  1861. 
  

  

  