﻿THE 
  MINING 
  AND 
  QUARRY 
  INDUSTRY 
  I908 
  25 
  

  

  are 
  a 
  few 
  producers 
  in 
  the 
  State 
  who 
  do 
  not 
  utihze 
  the 
  crude 
  clay 
  

   themselves, 
  but 
  ship 
  their 
  output 
  to 
  others 
  for 
  manufacture. 
  Some 
  

   of 
  the 
  material, 
  like 
  the 
  Albany 
  slip 
  clay 
  for 
  example, 
  is 
  even 
  

   shipped 
  to 
  points 
  without 
  the 
  State. 
  In 
  1908 
  returns 
  were 
  received 
  

   from 
  eight 
  producers 
  in 
  this 
  branch 
  of 
  the 
  industry 
  whose 
  total 
  

   shipments 
  amounted 
  to 
  4697 
  short 
  tons 
  valued 
  at 
  $11,605. 
  The 
  cor- 
  

   responding 
  total 
  for 
  1907 
  was 
  3927 
  short 
  tons 
  valued 
  at 
  $6163, 
  and 
  

   for 
  1906 
  it 
  was 
  5477 
  short 
  tons 
  with 
  a 
  value 
  of 
  $9125. 
  Besides 
  

   slip 
  clay 
  the 
  shipments 
  included 
  fire 
  clay, 
  brick 
  clay 
  and 
  the 
  white 
  

   clay 
  of 
  Staten 
  Island. 
  

  

  EMERY 
  

  

  There 
  was 
  a 
  large 
  falling 
  off 
  in 
  the 
  production 
  of 
  emery 
  last 
  

   year, 
  the 
  total 
  amounting 
  to 
  690 
  short 
  tons 
  valued 
  at 
  $8860 
  as 
  com- 
  

   pared 
  with 
  1223 
  short 
  tons 
  valued 
  at 
  $13,057 
  in 
  1907. 
  The 
  decrease 
  

   in 
  quantity 
  was 
  thus 
  533 
  tons 
  and 
  in 
  value 
  $4197. 
  The 
  output 
  was 
  

   also 
  smaller 
  than 
  in 
  any 
  recent 
  year 
  previously, 
  the 
  total 
  for 
  1906 
  

   having 
  been 
  1307 
  short 
  tons 
  valued 
  at 
  $13,870; 
  for 
  1905, 
  1475 
  

   short 
  tons 
  valued 
  at 
  $12,452 
  and 
  for 
  1904, 
  1148 
  short 
  tons 
  valued 
  

   at 
  $17,220. 
  The 
  statistics 
  have 
  been 
  based 
  on 
  the 
  crude 
  material 
  

   before 
  grinding 
  or 
  other 
  treatment 
  except 
  the 
  rough 
  cobbing 
  to 
  

   which 
  it 
  was 
  subjected 
  at 
  the 
  quarries. 
  The 
  rock 
  was 
  all 
  shipped 
  

   from 
  Peekskill 
  and 
  distributed 
  among 
  the 
  manufacturers 
  of 
  emery 
  

   wheels 
  and 
  other 
  emery 
  abrasives, 
  whose 
  plants 
  are 
  mainly 
  located 
  

   in 
  Pennsylvania. 
  

  

  The 
  list 
  of 
  producers 
  in 
  1908 
  included 
  : 
  Blue 
  Corundum 
  Min- 
  

   ing 
  Co., 
  Easton, 
  Pa. 
  ; 
  Keystone 
  Emery 
  Mills, 
  Frankford, 
  Pa. 
  ; 
  

   Tanite 
  Co., 
  Stroudsburg, 
  Pa., 
  and 
  J. 
  R. 
  Lancaster, 
  Peekskill. 
  The 
  

   total 
  emery 
  mined, 
  as 
  above 
  given, 
  exceeded 
  somewhat 
  the 
  ship- 
  

   ments 
  from 
  Peekskill, 
  as 
  these 
  amounted 
  to 
  579 
  short 
  tons. 
  

  

  The 
  emery 
  is 
  a 
  mixture 
  of 
  corundum, 
  spinel 
  and 
  magnetite, 
  the 
  

   corundum 
  of 
  course 
  being 
  the 
  ingredient 
  of 
  most 
  value. 
  It 
  occurs 
  

   as 
  a 
  very 
  hard 
  and 
  dense 
  rock, 
  of 
  dark 
  gray 
  to 
  nearly 
  black 
  color, 
  

   sometimes 
  showing 
  the 
  corundum 
  in 
  well 
  developed 
  prismatic 
  

   crystals 
  of 
  lighter 
  shade. 
  There 
  is 
  considerable 
  variation 
  in 
  regard 
  

   to 
  the 
  mineral 
  composition, 
  and 
  Magnus^ 
  who 
  examined 
  thin 
  sec- 
  

   tions 
  of 
  the 
  material 
  reports 
  that 
  in 
  some 
  specimens 
  the 
  corundum 
  

   constitutes 
  over 
  50 
  per 
  cent 
  of 
  the 
  mass, 
  while 
  in 
  others 
  it 
  is 
  al- 
  

   most 
  wanting. 
  The 
  emery 
  occurs 
  in 
  the 
  form 
  of 
  lenses 
  and 
  bands 
  

   within 
  an 
  area 
  of 
  gabbroic 
  intrusives 
  known 
  as 
  the 
  Cortlandt 
  

   series. 
  It 
  is 
  to 
  be 
  regarded, 
  doubtless, 
  as 
  a 
  segregation 
  of 
  the 
  

  

  ' 
  Abrasives 
  of 
  New 
  York. 
  N. 
  Y 
  State 
  Gaol. 
  23d 
  An. 
  Rep't. 
  1904. 
  

  

  