﻿366 
  A. 
  F. 
  Rogers 
  — 
  Miner 
  alogical 
  Notes. 
  

  

  crystals 
  of 
  the 
  same 
  mineral. 
  Several 
  such 
  specimens 
  in 
  the 
  

   University 
  of 
  Kansas 
  Museum, 
  the 
  exact 
  locality 
  of 
  which 
  is 
  

   unknown, 
  furnish 
  the 
  following 
  notes. 
  The 
  crystals 
  examined 
  

   are 
  of 
  three 
  different 
  habits 
  : 
  (1) 
  the 
  form 
  e 
  (0112)-i, 
  large 
  

   crystals 
  with 
  faces 
  striated 
  parallel 
  to 
  shorter 
  diagonal 
  of 
  the 
  

   faces 
  ; 
  (2) 
  the 
  form 
  e 
  /'(0221)-2, 
  small 
  to 
  medium 
  sized 
  crystals 
  ; 
  

   (3) 
  the 
  third 
  deserves 
  more 
  detailed 
  notice. 
  These 
  crystals 
  

   average 
  about 
  5 
  mm 
  in 
  diameter 
  and 
  present 
  the 
  following 
  

   uncommon 
  forms 
  : 
  Z 
  (0223)~f 
  and 
  % 
  (0772)-J- 
  , 
  represented 
  in 
  

   fig. 
  5. 
  The 
  faces 
  are 
  dull 
  and 
  a 
  little 
  rough 
  so 
  that 
  no 
  

   measurements 
  were 
  possible 
  with 
  the 
  reflecting 
  goniometer. 
  

   Measurements 
  with 
  the 
  contact 
  goniometer 
  were 
  as 
  follows 
  : 
  

  

  Limits. 
  Average. 
  Calculated. 
  

  

  Z 
  A 
  Z 
  (0223 
  /s 
  0223) 
  6 
  measurements 
  56°-57° 
  30' 
  56°35' 
  56°50' 
  

   Z^x 
  (0223^0772) 
  6 
  " 
  40° 
  30'-42° 
  41° 
  08' 
  40° 
  31' 
  

  

  The 
  % 
  f 
  aces 
  are 
  triangular 
  in 
  shape 
  and 
  in 
  consequence 
  the 
  

   embedded 
  crystals 
  with 
  the 
  Z 
  faces 
  partially 
  concealed 
  have 
  

   somewhat 
  the 
  appearance 
  of 
  regular 
  octahedra. 
  

  

  Mineralogical 
  Laboratory, 
  University 
  of 
  Kansas. 
  

  

  