﻿368 
  W. 
  F. 
  Foshag 
  — 
  Apthitalite 
  from 
  California. 
  

  

  K 
  32-46 
  

  

  Na 
  9-01 
  

  

  S0 
  4 
  53-71 
  

  

  CI 
  4-76 
  

  

  H 
  o 
  010 
  

  

  10004 
  

  

  or 
  K,S0 
  4 
  72-37%, 
  Na 
  2 
  S0 
  4 
  18-38%, 
  NaCl 
  7-87%, 
  or 
  a 
  

   ratio 
  of 
  K 
  2 
  S0 
  4 
  : 
  Na 
  2 
  S0 
  4 
  of 
  about 
  4:1. 
  

  

  This 
  is 
  the 
  first 
  reported 
  occurrence 
  of 
  apthitalite 
  in 
  

   the 
  United 
  States 
  as 
  far 
  as 
  the 
  writer 
  is 
  aware 
  and 
  is 
  

   interesting 
  in 
  that 
  it 
  is 
  the 
  first 
  potassium 
  mineral 
  re- 
  

   ported 
  from 
  Searles 
  Lake. 
  The 
  mineral 
  is 
  also 
  found 
  

   sparingly 
  at 
  Stassfurt 
  and 
  Kaluscz 
  and 
  is 
  the 
  only 
  rare 
  

   mineral 
  common 
  to 
  all 
  three 
  of 
  these 
  remarkable 
  saline 
  

   deposits. 
  The 
  Searles 
  Lake 
  mineral 
  is 
  directly 
  asso- 
  

   ciated 
  with 
  halite 
  in 
  well-defined 
  octahedral 
  crystals 
  and 
  

   rests 
  upon 
  a 
  mass 
  of 
  borax 
  which 
  has 
  been 
  transformed 
  

   by 
  atmospheric 
  exposure 
  to 
  a 
  white 
  pulverulent 
  mass. 
  

   The 
  apthitalite 
  itself 
  however 
  shows 
  no 
  alteration 
  what- 
  

   ever. 
  

  

  United 
  States 
  National 
  Museum, 
  

   Washington, 
  D. 
  C. 
  

  

  

  