﻿414 
  Penfield 
  and 
  Foote 
  — 
  Itceblingite, 
  a 
  new 
  Silicate. 
  

  

  SiO„ 
  

  

  so 
  . 
  

  

  Found. 
  

  

  23-8 
  

  

  .. 
  _.. 
  91 
  

  

  Theory. 
  

  

  22-1 
  

  

  9*4 
  

  

  PbO 
  

  

  31*3 
  

  

  32-9 
  

  

  CaO 
  

  

  HO 
  

  

  29-4 
  

  

  ... 
  .. 
  6-4 
  

  

  - 
  29-0 
  

   6'6 
  

  

  

  

  

  100-0 
  100-0 
  

  

  There 
  must 
  be 
  some 
  question 
  as 
  to 
  the 
  exact 
  formula 
  of 
  the 
  

   mineral, 
  for 
  the 
  one 
  proposed 
  is 
  complicated 
  and 
  the 
  agree- 
  

   ment 
  between 
  the 
  results 
  of 
  the 
  analysis 
  and 
  the 
  theory 
  is 
  not 
  

   so 
  close 
  as 
  one 
  would 
  desire. 
  It 
  is 
  not 
  probable, 
  however, 
  that 
  

   the 
  mineral 
  is 
  a 
  mixture, 
  or, 
  at 
  least, 
  that 
  it 
  contains 
  much 
  

   foreign 
  material. 
  If 
  it 
  were 
  a 
  mixture, 
  one 
  would 
  expect 
  the 
  

   presence 
  of 
  some 
  heavy 
  lead 
  mineral, 
  considerably 
  above 
  3*43 
  in 
  

   specific 
  gravity, 
  with 
  a 
  lighter 
  calcium 
  silicate. 
  In 
  order 
  to 
  

   test 
  this 
  point 
  some 
  of 
  the 
  material 
  was 
  powdered, 
  sifted 
  to 
  a 
  

   uniform 
  grain 
  and 
  placed 
  in 
  methylen 
  iodide 
  with 
  a 
  specific 
  

   gravity 
  of 
  3*29 
  when 
  all 
  of 
  the 
  powder 
  sank. 
  It 
  is 
  thus 
  very 
  

   definitely 
  proved 
  that 
  wollastonite 
  (specific 
  gravity 
  2*9) 
  or 
  any 
  

   related 
  calcium 
  silicate 
  is 
  absent. 
  

  

  The 
  special 
  points 
  of 
  interest 
  connected 
  with 
  this 
  mineral 
  

   are 
  that 
  this 
  is 
  the 
  first 
  time 
  that 
  a 
  sulphite 
  has 
  been 
  observed 
  

   in 
  nature, 
  and 
  that 
  silicates 
  containing 
  lead 
  are 
  very 
  rare, 
  hav- 
  

   ing 
  been 
  observed 
  up 
  to 
  the 
  present 
  time 
  in 
  only 
  a 
  few 
  locali- 
  

   ties 
  in 
  Sweden. 
  

  

  The 
  mineral 
  fuses 
  before 
  the 
  blowpipe 
  at 
  about 
  3 
  to 
  a 
  gray 
  

   globule, 
  and 
  gives 
  the 
  pale 
  blue 
  flame 
  of 
  lead, 
  which 
  ceases 
  

   after 
  heating 
  for 
  some 
  time. 
  On 
  charcoal 
  with 
  sodium 
  car- 
  

   bonate 
  in 
  the 
  reducing 
  flame, 
  lead 
  globules 
  and 
  a 
  coating 
  of 
  

   lead 
  oxide 
  are 
  produced, 
  and 
  the 
  residue 
  reacts 
  on 
  silver 
  for 
  

   sulphur. 
  With 
  the 
  fluxes, 
  the 
  reactions 
  for 
  manganese 
  are 
  ob- 
  

   tained. 
  In 
  the 
  closed 
  tube, 
  water 
  is 
  given 
  off. 
  The 
  powdered 
  

   mineral 
  is 
  dissolved 
  with 
  ease 
  in 
  acids, 
  even 
  when 
  very 
  dilute, 
  

   and 
  gelatinous 
  silica 
  is 
  obtained 
  upon 
  evaporation. 
  The 
  odor 
  

   of 
  sulphurous 
  anhydride 
  may 
  be 
  obtained 
  when 
  the 
  mineral 
  is 
  

   dissolved 
  in 
  a 
  little 
  hydrochloric 
  acid, 
  but 
  this 
  test 
  is 
  not 
  very 
  

   apparent. 
  

  

  Concerning 
  the 
  occurrence 
  of 
  the 
  mineral, 
  the 
  following 
  

   information 
  has 
  been 
  received 
  from 
  Mr. 
  Nason 
  : 
  The 
  mineral 
  

   occurs 
  at 
  the 
  one 
  thousand 
  foot 
  level, 
  in 
  or 
  near 
  the 
  contact 
  

   between 
  granite 
  and 
  white 
  limestone, 
  where 
  great 
  veins 
  and 
  

   bunches 
  of 
  garnet 
  rock 
  are 
  found. 
  The 
  associated 
  minerals 
  

   are 
  garnet, 
  titanite, 
  zircon, 
  phlogopite, 
  axinite 
  both 
  massive 
  

   and 
  in 
  drusy 
  crystals, 
  willemite 
  in 
  small,- 
  green, 
  transparent 
  

   crystals, 
  datolite, 
  barite, 
  caswellite, 
  calcite, 
  arsenopyrite, 
  sphal- 
  

   erite, 
  rhodonite 
  and 
  rbodochrosite. 
  The 
  axinite, 
  which 
  occurs 
  

  

  