﻿52 
  Hess 
  and 
  Hunt 
  — 
  Trip 
  lite 
  from 
  Eastern 
  Nevada. 
  

  

  Chemical 
  properties. 
  — 
  As 
  considerable 
  material 
  was 
  at 
  hand, 
  

   by 
  exercising 
  some 
  care 
  in 
  freeing 
  the 
  mineral 
  from 
  its 
  associ- 
  

   ates 
  four 
  or 
  five 
  grams 
  of 
  the 
  pure 
  substance 
  was 
  easily 
  

   obtained 
  for 
  a 
  chemical 
  examination. 
  Qualitative 
  tests 
  hav- 
  

   ing 
  established 
  the 
  composition 
  as 
  essentially 
  a 
  manganese- 
  

   fluo- 
  phosphate, 
  a 
  quantitative 
  analysis 
  was 
  undertaken 
  to 
  

   determine 
  the 
  particular 
  species. 
  

  

  The 
  fluorine 
  was 
  determined 
  according 
  to 
  the 
  Fresenius 
  

   method, 
  by 
  which 
  the 
  silicon 
  fluoride 
  liberated 
  by 
  the 
  action 
  

   of 
  concentrated 
  sulphuric 
  acid 
  and 
  silica 
  is 
  absorbed 
  in 
  a 
  train 
  

   of 
  U-tubes 
  containing, 
  respectively, 
  moistened 
  pumice, 
  soda 
  

   lime, 
  and 
  calcium 
  chloride. 
  The 
  phosphoric 
  acid 
  was 
  weighed 
  

   as 
  magnesium 
  pyrophosphate 
  after 
  previous 
  precipitation 
  as 
  

   ammonium 
  phosphomolybdate. 
  The 
  manganese 
  was 
  precipi- 
  

   tated 
  as 
  NH 
  4 
  MnP0 
  4 
  after 
  dissolving 
  the 
  first 
  precipitate 
  of 
  the 
  

   oxide. 
  The 
  minor 
  constituents, 
  ferrous 
  iron, 
  calcium, 
  and 
  

   magnesium, 
  were 
  estimated 
  in 
  the 
  usual 
  manner. 
  In 
  the 
  analy- 
  

   sis, 
  separate 
  samples 
  were 
  taken 
  for 
  the 
  individual 
  determina- 
  

   tions 
  with 
  the 
  exception 
  of 
  calcium 
  and 
  magnesium. 
  Ferric 
  

   iron, 
  water, 
  and 
  the 
  alkalies 
  were 
  absent. 
  

  

  The 
  results 
  of 
  the 
  above 
  methods 
  gave 
  : 
  

  

  -O 
  

  

  MdO.. 
  

  

  57-63 
  

  

  MnO.... 
  

  

  43-13 
  

  

  FeO 
  .. 
  

  

  1-68 
  

  

  FeO 
  .... 
  

  

  1-68 
  

  

  CaO.._ 
  

  

  2-86 
  

  

  CaO 
  .... 
  

  

  2-86 
  

  

  MgO.. 
  

  

  1-21 
  or 
  

  

  MgO 
  ... 
  

  

  1-21 
  

  

  PA 
  ... 
  

  

  31-84 
  

  

  PA--- 
  - 
  

  

  31-84 
  

  

  F 
  

  

  7-77 
  

  

  MnF 
  2 
  ... 
  

  

  19-00 
  

  

  

  102-99 
  

  

  99-72 
  

  

  = 
  F 
  ... 
  

  

  3-27 
  

  

  

  

  mol. 
  l 
  

  

  atio 
  

  

  •608] 
  

  

  

  •023 
  I 
  

   •051 
  f 
  

  

  •712 
  = 
  3-17 
  

  

  •030 
  J 
  

  

  

  •224 
  

  

  •224 
  = 
  1- 
  

  

  •204 
  

  

  •204 
  = 
  -91 
  

  

  99-72 
  

  

  Approximately 
  in 
  whole 
  numbers 
  3:1:1 
  or 
  3MnO.P 
  2 
  5 
  . 
  

   MnF 
  2 
  . 
  The 
  deviation 
  from 
  the 
  theoretical 
  composition 
  is 
  

   probably 
  due 
  to 
  the 
  somewhat 
  unsatisfactory 
  fluorine 
  deter- 
  

   mination, 
  for 
  with 
  a 
  slight 
  increase 
  in 
  the 
  fluorine 
  there 
  would 
  

   result 
  in 
  the 
  recalculated 
  percentage 
  a 
  decrease 
  in 
  the 
  MnO. 
  

   The 
  similarity 
  of 
  the 
  derived 
  formula 
  to 
  the 
  one 
  generally 
  

   accepted 
  for 
  triplite 
  is 
  easily 
  recognized. 
  Reference 
  to 
  the 
  

   literature, 
  however, 
  reveals 
  a 
  considerable 
  variation 
  in 
  the 
  

   composition 
  of 
  this 
  mineral, 
  as 
  shown 
  by 
  the 
  following 
  table 
  :* 
  

  

  * 
  As 
  some 
  of 
  the 
  earlier 
  analysts 
  overlooked 
  the 
  fluorine, 
  their 
  analyses 
  

   have 
  not 
  been 
  included. 
  

  

  