﻿7tt 
  Loughlin 
  and 
  Schaller 
  — 
  Crandallite, 
  a 
  New 
  Mineral. 
  

  

  by 
  Lindgren* 
  as 
  a 
  basic 
  hydrous 
  strontium 
  sulphate 
  which 
  occurs 
  

   as 
  an 
  impalpable 
  white 
  powder 
  covering 
  granular 
  celestite, 
  in 
  a 
  

   vein 
  on 
  level 
  7 
  of 
  the 
  Ironclad 
  ?*Iine, 
  Cripple 
  Creek, 
  Colorado. 
  

   Under 
  the 
  microscope 
  the 
  mineral 
  was 
  seen 
  to 
  consist 
  of 
  short 
  

   and 
  extremely 
  delicate 
  white 
  fibers 
  of 
  very 
  feeble 
  double 
  

   refraction 
  and 
  an 
  extinction 
  which 
  is 
  probably 
  parallel. 
  An 
  

   analysis 
  by 
  W. 
  T. 
  Schaller 
  of 
  a 
  very 
  small 
  quantity 
  gave 
  : 
  

   SrO, 
  25-1 
  ; 
  CaO, 
  151 
  ; 
  A1„0„ 
  13-9 
  ; 
  MgO, 
  2-5 
  ; 
  S0 
  3 
  , 
  13-9 
  ; 
  

   H 
  2 
  (107°), 
  ; 
  H 
  2 
  (ignition), 
  24*1 
  ; 
  total, 
  91*6. 
  No 
  water 
  

   was 
  lost 
  at 
  100° 
  and 
  at 
  260° 
  only 
  1*49 
  per 
  cent 
  H,0 
  was 
  

   driven 
  off. 
  No 
  test 
  for 
  phosphoric 
  acid 
  was 
  made 
  and 
  the 
  

   material 
  was 
  too 
  limited 
  in 
  quantity 
  and 
  of 
  too 
  undetermined 
  

   purity 
  for 
  these 
  figures 
  to 
  have 
  much 
  more 
  than 
  a 
  qualitative 
  

   value. 
  

  

  The 
  relations 
  of 
  these 
  minerals, 
  especially 
  of 
  the 
  fibrous 
  

   ones 
  to 
  those 
  not 
  fibrous 
  (those 
  of 
  the 
  alunite-beudantite 
  group), 
  

   are 
  not 
  at 
  all 
  clear, 
  but 
  the 
  composition 
  of 
  crandallite 
  seems 
  to 
  

   indicate 
  that 
  there 
  is 
  a 
  definite 
  group 
  of 
  fibrous 
  minerals 
  

   which 
  are 
  closely 
  related 
  in 
  the 
  type 
  of 
  formula 
  to 
  those 
  of 
  the 
  

   alunite-beudantite 
  group 
  and 
  yet 
  seem 
  to 
  be 
  very 
  distinct 
  there- 
  

   from 
  and 
  to 
  probably 
  result 
  from 
  their 
  alteration. 
  

  

  * 
  Lindgren, 
  W., 
  and 
  Ransonie, 
  F. 
  L., 
  Geology 
  and 
  gold 
  deposits 
  of 
  the 
  

   Cripple 
  Creek 
  district, 
  Colorado. 
  U. 
  S. 
  Geol. 
  Survey, 
  Prof. 
  Paper 
  54, 
  

   p. 
  125, 
  286, 
  1906. 
  

  

  