DEVELOPED  PHOSPHATE  DEPOSITS  OF  NORTH- 
ERN ARKANSAS. 
By  A.  H.  Purdue. 
INTRODUCTION. 
The  field  work  for  this  paper  was  done  in  the  latter  part  of  August 
and  the  first  part  of  September,  1906.  Previous  to  this  time  (in 
the  latter  part  of  1903)  the  writer  made  a  visit  to  the  developed 
deposits  for  the  purpose  of  arranging  for  an  exhibit  of  the  phos- 
phate rock  and  its  products  at  the  Louisiana  Purchase  Exposition. 
The  company  operating  the  mines  and  the  fertilizer  plant  connected 
therewith  freely  assisted  in  preparing  an  exhibit  and,  among  other 
things,  shipped  to  the  exposition  a  solid  block  of  phosphate  rock 
4  feet  wide,  8  feet  long,  and  somewhat  more  than  4  feet  thick.  This 
block  of  stone  attracted  the  attention  of  those  who  were  interested 
in  the  fertilizers  and  phosphate  deposits  of  the  country  and  excited 
special  interest  in  the  deposits  of  Arkansas,  an  interest  that  justifies 
the  preparation  of  the  present  paper. 
The  area  over  which  the  phosphate  deposits  of  northern  Arkansas 
occur  is  mentioned  in  the  following  reports  of  previous  writers: 
Owen,  David  Dale.  First  report  of  a  geological  reconnaissance  in  the  northern 
counties  of  Arkansas,  made  during  the  years  1857  and  1858.     1858. 
Penrose,  II.  A.  F.  Manganese;  its  uses,  ores,  and  deposits:  Ann.  Kept.  Geol.  Sur- 
vey Arkansas  for  1890,  vol.  1. 
Hopkins,  T.  0.  Marbles  and  other  limestones:  Ann.  Rept.  Geol.  Survey  Arkan- 
sas for  1890,  vol.  4. 
Branner,  J.  C.  (State  geologist).  The  lead  and  zinc  region  of  northern  Arkansas: 
Ann.  Rept.  Geol.  Survey  Arkansas  for  1892,  vol.  5. 
Branner,  J.  C.  The  phosphate  deposits  of  Arkansas:  Trans.  Am.  Inst.  Min.  Eng., 
vol.  26,  1896,  pp.  580-598. 
Branner,  J.  C,  and  Newsom,  J.  F.  The  phosphate  rocks  of  Arkansas:  Bull. 
Arkansas  Agr.  Exp.  Station  No.  74,  1902. 
Ulrich,  E.  O.,  and  others.  Zinc  and  lead  deposits  of  northern  Arkansas:  Prof. 
Paper  U.  S.  Geol.  Survey  No.  24,  1904,  p.  100. 
GEOGRAPHY  AND  HISTORY  OF  THE  PHOSPHATE  BEDS. 
Geographic  distribution  of  the  beds. — The  developed  phosphate  depos- 
its of  Arkansas  are  on  LafTerty  Creek,  on  the  western  edge  of  Independ- 
ence County.     The  only  point  at  which  the  beds  are  now  worked  is 
463 
