﻿152 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  the 
  magnetite. 
  The 
  latter 
  being 
  commonly 
  in 
  excess 
  constitutes 
  the 
  

  

  ground 
  mass 
  through 
  which 
  the 
  ilmenite 
  is 
  more 
  or 
  less 
  regularly 
  

  

  distributed 
  in 
  grains 
  of 
  fairly 
  even 
  size. 
  

  

  A 
  partial 
  separation 
  of 
  the 
  magnetite 
  and 
  ilmenite 
  was 
  obtained 
  

  

  with 
  the 
  ore 
  from 
  the 
  Sanford 
  pit 
  at 
  Lake 
  Sanford. 
  A 
  sample 
  was 
  

  

  crushed 
  through 
  a 
  40 
  mesh 
  sieve 
  and 
  the 
  magnetite 
  removed 
  with 
  

  

  a 
  small 
  hand 
  magnet. 
  The 
  results 
  from 
  chemical 
  analysis 
  of 
  the 
  

  

  crude 
  ore 
  (1), 
  magnetite 
  concentrate 
  (2) 
  and 
  the 
  ilmenite 
  and 
  other 
  

  

  residual 
  minerals 
  (3) 
  are 
  given 
  herewith. 
  The 
  analyses 
  were 
  made 
  

  

  by 
  E. 
  W. 
  Morley. 
  

  

  1 
  2 
  3 
  

  

  Fe 
  2 
  3 
  55-9 
  54-39 
  14.28 
  

  

  FeO 
  27.5 
  28.66 
  30.93 
  

  

  Ti0 
  2 
  14 
  8.93 
  45-23 
  

  

  It 
  will 
  be 
  observed 
  that 
  the 
  magnetite 
  concentrate 
  still 
  contains 
  

   a 
  considerable 
  proportion 
  of 
  titanium, 
  mostly 
  due, 
  no 
  doubt, 
  to 
  

   the 
  inclusion 
  of 
  particles 
  of 
  mixed 
  character. 
  By 
  crushing 
  still 
  

   finer 
  a 
  cleaner 
  separation 
  may 
  be 
  made, 
  as 
  has 
  been 
  demonstrated 
  

   for 
  the 
  same 
  ore 
  in 
  recent 
  experiments 
  that 
  are 
  described 
  on 
  a 
  sub- 
  

   sequent 
  page. 
  The 
  analyses 
  are 
  not 
  reducible 
  to 
  simple 
  terms 
  of 
  

   magnetite 
  and 
  ilmenite, 
  and 
  further 
  work 
  is 
  needed 
  before 
  the 
  chem- 
  

   ical 
  relations 
  can 
  be 
  fully 
  stated. 
  It 
  is 
  quite 
  likely 
  that 
  the 
  mag- 
  

   netite 
  itself 
  carries 
  a 
  proportion 
  of 
  the 
  titanium, 
  in 
  which 
  case 
  the 
  

   entire 
  removal 
  of 
  the 
  latter 
  would 
  be 
  impossible. 
  

  

  The 
  remaining 
  minerals 
  found 
  in 
  the 
  titaniferous 
  ores 
  include 
  

   plagioclase, 
  pyroxene, 
  hornblende, 
  biotite, 
  olivine, 
  garnet, 
  pyrite, 
  

   apatite, 
  spinel 
  and 
  quartz. 
  The 
  plagioclase 
  is 
  usually 
  labradorite 
  

   or 
  an 
  allied 
  variety. 
  Both 
  orthorhombic 
  and 
  monocline 
  pyroxenes 
  

   are 
  represented. 
  Olivine 
  is 
  rather 
  rare 
  in 
  the 
  Adirondack 
  ores 
  so 
  

   far 
  as 
  observed. 
  Pyrite 
  is 
  a 
  fluctuating 
  constituent, 
  more 
  abundant 
  

   in 
  the 
  ores 
  that 
  are 
  included 
  by 
  gabbro 
  than 
  in 
  those 
  found 
  within 
  

   anorthosite. 
  Spinel 
  has 
  not 
  been 
  certainly 
  identified, 
  but 
  its 
  pres- 
  

   ence 
  is 
  strongly 
  indicated 
  by 
  the 
  analyses 
  which 
  show 
  an 
  excess 
  of 
  

   A1 
  2 
  3 
  over 
  the 
  amounts 
  required 
  for 
  the 
  silicates. 
  The 
  analyses 
  of 
  

   concentrates 
  on 
  page 
  154 
  are 
  suggestive 
  also 
  in 
  that 
  connection. 
  

   Apatite 
  is 
  present 
  in 
  minute 
  quantities 
  only, 
  and 
  the 
  ores 
  are 
  con- 
  

   sequently 
  low 
  in 
  phosphorus. 
  

  

  The 
  order 
  of 
  crystallization 
  of 
  the 
  minerals 
  revealed 
  by 
  study 
  of 
  

   the 
  etched 
  surfaces 
  is 
  as 
  follows: 
  1, 
  silicates; 
  2, 
  pyrite; 
  3, 
  ilmenite 
  

   and 
  magnetite. 
  

  

  The 
  order 
  is 
  thus 
  the 
  reverse 
  of 
  the 
  normal 
  one 
  for 
  igneous 
  rocks 
  

   in 
  which 
  the 
  silicates 
  predominate 
  over 
  the 
  iron 
  ores. 
  The 
  expla- 
  

  

  