﻿ADIRONDACK 
  MAGNETIC 
  IRON 
  ORES 
  147 
  

  

  in 
  Essex 
  and 
  southern 
  Franklin 
  counties 
  and 
  consists 
  of 
  a 
  connected 
  

   mass 
  which 
  spreads 
  over 
  a 
  surface 
  of 
  some 
  1 
  200 
  square 
  miles. 
  There 
  

   are 
  smaller 
  outlying 
  intrusions 
  in 
  Clinton 
  and 
  Warren 
  counties 
  and 
  

   in 
  the 
  western 
  Adirondack 
  region. 
  The 
  greater 
  number 
  of 
  deposits 
  

   are 
  found 
  within 
  the 
  bordering 
  portions 
  of 
  the 
  main 
  anorthosite 
  

   area 
  in 
  the 
  townships 
  of 
  Westport, 
  Elizabethtown 
  and 
  Newcomb, 
  

   Essex 
  co. 
  In 
  the 
  central 
  part 
  no 
  large 
  bodies 
  are 
  known. 
  A 
  

   deposit 
  near 
  Port 
  Leyden, 
  Lewis 
  co., 
  is 
  the 
  only 
  occurrence 
  outside 
  

   of 
  the 
  main 
  area 
  that 
  has 
  been 
  the 
  object 
  of 
  exploitation. 
  

  

  General 
  geological 
  relations 
  and 
  origin 
  of 
  the 
  deposits 
  

  

  The 
  titaniferous 
  deposits 
  constitute 
  a 
  well 
  marked 
  type 
  of 
  ore 
  

   occurrence 
  that 
  is 
  quite 
  widely 
  distributed 
  in 
  this 
  and 
  foreign 
  

   countries. 
  They 
  are 
  known 
  to 
  be 
  of 
  considerable 
  extent 
  in 
  Minne- 
  

   sota, 
  Wyoming 
  and 
  Colorado, 
  in 
  the 
  Provinces 
  of 
  Ontario 
  and 
  

   Quebec, 
  and 
  in 
  Sweden, 
  Norway 
  and 
  Brazil. 
  The 
  Taberg 
  deposit 
  

   in 
  Sweden 
  was 
  mined 
  for 
  a 
  number 
  of 
  years 
  and 
  the 
  ore 
  used 
  for 
  the 
  

   manufacture 
  of 
  iron. 
  The 
  various 
  localities 
  for 
  titaniferous 
  

   magnetites 
  have 
  been 
  described 
  briefly 
  in 
  a 
  paper 
  by 
  Professor 
  

   Kemp. 
  1 
  The 
  occurrences 
  throughout 
  show 
  a 
  remarkable 
  degree 
  

   of 
  uniformity 
  in 
  the 
  essential 
  features 
  of 
  their 
  geological 
  surround- 
  

   ings 
  and 
  composition 
  of 
  the 
  ores. 
  

  

  With 
  a 
  single 
  exception 
  the 
  country 
  rocks 
  of 
  the 
  Adirondack 
  

   deposits, 
  as 
  is 
  generally 
  the 
  case 
  elsewhere, 
  are 
  members 
  of 
  the 
  

   gabbro 
  family. 
  The 
  prevailing 
  rock 
  in 
  the 
  Adirondack 
  region 
  

   is 
  the 
  variety 
  known 
  as 
  anorthosite, 
  the 
  predominant 
  constituent 
  

   of 
  which 
  is 
  a 
  basic 
  plagioclase 
  feldspar, 
  usually 
  labradorite. 
  The 
  

   rock 
  is 
  the 
  first 
  of 
  a 
  series 
  of 
  related 
  intrusions 
  in 
  the 
  region 
  that 
  

   were 
  derived 
  apparently 
  from 
  a 
  common 
  magma. 
  Gabbro 
  in 
  

   the 
  restricted 
  sense, 
  syenite 
  and 
  probably 
  granite 
  are 
  represented 
  

   among 
  the 
  later 
  intrusions 
  derived 
  from 
  the 
  same 
  source. 
  Most 
  

   of 
  the 
  deposits 
  are 
  found 
  within 
  dikes 
  and 
  masses 
  of 
  gabbro 
  which 
  

   occur 
  at 
  intervals 
  throughout 
  the 
  anorthosite 
  area. 
  Some 
  of 
  the 
  

   large 
  bodies 
  at 
  Lake 
  Sanford, 
  however, 
  are 
  inclosed 
  directly 
  by 
  

   the 
  anorthosite. 
  

  

  The 
  general 
  characters 
  of 
  the 
  gabbros 
  and 
  anorthosites 
  have 
  

   already 
  been 
  set 
  forth 
  in 
  the 
  part 
  of 
  this 
  report 
  relating 
  to 
  Adiron 
  

   dack 
  geology. 
  The 
  following 
  analyses 
  taken 
  from 
  Professor 
  

   Kemp's 
  paper 
  give 
  details 
  as 
  to 
  the 
  chemical 
  composition 
  of 
  typ- 
  

  

  Z 
  A 
  Brief 
  Review 
  of 
  the 
  Titaniferous 
  Magnetites. 
  Columbia 
  Univ. 
  Sch. 
  of 
  

   Mines 
  Quarterly, 
  July 
  1899. 
  

  

  