﻿ECONOMIC 
  GEOLOGY 
  219 
  

  

  in 
  operation 
  in 
  1801 
  and 
  1802, 
  and 
  they 
  were 
  run 
  upon 
  the 
  ores 
  

   in 
  their 
  vicinity. 
  But 
  the 
  output 
  was 
  small, 
  in 
  the 
  aggregate 
  a 
  

   few 
  thousands 
  of 
  tons. 
  The 
  rapid 
  increase 
  was 
  after 
  1840. 
  

  

  THE 
  HEMATITE 
  ORES 
  OF 
  ST 
  LAWRENCE 
  AND 
  JEFFER- 
  

   SON 
  COUNTIES 
  

  

  Tlie 
  hematites, 
  or 
  red 
  hematites, 
  as 
  diistinguished 
  from 
  the 
  

   brown 
  hematites 
  (limonites) 
  are 
  mined 
  in 
  a 
  narrow 
  belt, 
  scarcely 
  

   30 
  miles 
  long, 
  stretching 
  from 
  Philadelphia, 
  in 
  Jefferson 
  county, 
  

   northeast 
  into 
  Hermon, 
  in 
  St 
  Lawrence 
  county. 
  The 
  ore 
  de- 
  

   posits 
  are 
  found 
  associated 
  with 
  a 
  so-called 
  serpentine 
  rock, 
  and 
  

   lying 
  between 
  the 
  Potsdam 
  sandstone 
  and 
  the 
  crystalline 
  rocks 
  

   of 
  the 
  Archaean 
  age. 
  

  

  The 
  hematite 
  of 
  these 
  mines 
  is 
  generally 
  firm 
  and 
  massive, 
  of 
  a 
  

   deep 
  red 
  color, 
  soiling 
  whatever 
  it 
  touches. 
  In 
  some 
  of 
  the 
  mines 
  

   there 
  is 
  a 
  specular 
  ore, 
  which 
  has 
  a 
  crystalline 
  structure, 
  metallic 
  

   lustre 
  and 
  is 
  of 
  a 
  steel-gray 
  to 
  black 
  color. 
  Calcite, 
  carbonate 
  of 
  

   iron, 
  ferruginous 
  quartz, 
  pyrite 
  and 
  millerite 
  occur 
  in 
  the 
  ore. 
  

   These 
  ores 
  average 
  from 
  48 
  to 
  53^ 
  of 
  metallic 
  iron. 
  They 
  con- 
  

   tain 
  an 
  excess 
  of 
  phosphorus 
  above 
  the 
  limit 
  demanded 
  by 
  furnace 
  

   managers 
  for 
  making 
  Bessemer 
  iron. 
  For 
  mixing 
  with 
  more 
  re- 
  

   fractory 
  ores 
  they 
  are 
  sought 
  after, 
  being 
  almost 
  self 
  -fluxing. 
  In 
  

   the 
  market 
  they 
  are 
  often 
  known 
  as 
  * 
  Antwerp 
  red 
  hematites 
  ' 
  and 
  

   * 
  Rossie 
  hematites.' 
  

  

  Charcoal 
  furnaces 
  were 
  built 
  early 
  in 
  this 
  century 
  at 
  Rossie, 
  

   St 
  Lawrence 
  county, 
  and 
  at 
  Sterlingville 
  and 
  Antwerp, 
  in 
  Jeffer- 
  

   son 
  county, 
  for 
  smelting 
  these 
  ores. 
  

  

  THE 
  CLINTON 
  OR 
  FOSSIL 
  ORES 
  

  

  The 
  red 
  hematite 
  of 
  the 
  Clinton 
  group 
  bears 
  several 
  names; 
  

   from 
  its 
  aggregated 
  grains 
  it 
  is 
  termed 
  ^ 
  oolitic 
  ore 
  ' 
  or 
  

   ^ 
  lenticular 
  iron 
  ore; 
  ' 
  from 
  its 
  fossiliferous 
  character, 
  it 
  is 
  widely 
  

   known 
  as 
  ^ 
  fossil 
  ore,' 
  and 
  from 
  its 
  place 
  in 
  the 
  geological 
  series, 
  

   it 
  is 
  often 
  called 
  ^ 
  Clinton 
  ore.' 
  It 
  is 
  remarkable 
  for 
  the 
  thin, 
  yet 
  

   persistent 
  beds 
  over 
  wide 
  areas^ 
  which 
  lie 
  between 
  green 
  shales 
  

   and 
  calcareous 
  strata. 
  Following 
  the 
  outcrop 
  of 
  the 
  Clinton 
  

   group, 
  the 
  ore 
  has 
  been 
  found 
  in 
  Herkimer, 
  Oneida, 
  Madison, 
  

  

  