MINERAL   PAINTS 
SOUTHERN   RED   HEMATITE  AS  AN   [NGREDI- 
ENT  OF   METALLIC  PAINT. 
By  ERN]  st   I'.  Burchard. 
INTRODUCTION. 
At  certain  localities  in  northwestern  Georgia  and  southeastern 
Tennessee  the  Clinton  oolitic  hematite  occurs  in  beds  too  thin  to  be 
profitably  mined  as  iron  ore  under  present  conditions.  Much  of  this 
red  ore  is  of  the  "soft"  variety  and  contains  an  unusually  lii^h 
percentage  of  ferric  oxide,  with  but  little  silica  and  alumina  and 
practically  no  lime.  Its  chemical  composition  fenders  it  an  ideal 
red-paint  material  and.  owing  to  its  physical  condition,  it  is  easily 
crushed  and  ground.  With  the  rapid  increase  <>f  building  in  the 
South,  together  with  the  manufacture  of  railroad  cars  and  structural 
iron,  has  come  a  demand  for  metallic  paint  that  has  given  these  beds 
of  ore  an  unexpected  importance. 
The  reasons  why  this  ore  can  be  profitably  mined  for  paint  material 
and  not  for  iron  making  are  briefly  these.  In  order  to  bring  the  cost. 
of  production  within  the  limits  of  market  prices  of  smelting  ores,  min- 
ing must  be  conducted  on  a  scale  involving  the  use  of  power,  cables; 
and  general  mine  equipment,  and  usually  a  railroad  spur  a  mile  or 
more  in  length  would  have  to  be  built.  The  total  amount  of  ore  in 
sighl  indicates  that  the  beds  would  be  exhausted  too  soon  to  warrant 
this  outlay.  Furthermore,  the  nature  of  the  deposits  is  likely  to  be 
such  thai  a  larger  quantity  of  shale  than  ore  would  have  to  be  removed 
either  to  win  the  ore  or  to  provide  the  head  room  necessary  for  regular 
mine  work,  thereby  rendering  it  doubtful  whet  her  the  ore  could  profit- 
ably be  worked  for  iron,  even  if  the  quantity  in  sighl  were  assuredly 
greater.  When  the  right  kind  of  ore  occurs  under  these  conditions, 
it  is  sufficiently  valuable  to  paint  manufacturers  to  bear  the  cost  of 
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