158  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,   1906,  PART    I. 
old  Parrish  mines,  now  being  reopened  by  the  Sheffield  Coal  and  Iron' 
Company.  The  ore  here  is  strictly  of  a  placer  type,  but  the  under-j 
lying  limestone  and  residual  clay  have  been  exposed  in  the  old  work- 
ings.    This  company  smelts  its  own  ore  at  Sheffield. 
The  third  system  of  mines  active  in  1906  is  operated  by  the  Alabama-; 
Virginia  Iron  Ore  Company  in  the  SW.  \  sec.  3  and  the  NW.  \  sec.  10,i 
T.  7  S.,  R.  12  W.  The  ore  at  this  point  is  gravelly  and  belongs  to  type 
B.  It  occurs  in  high  banks  having  at  their  bases  irregular  masses  of 
weathered  limestone  and  residual  clay.  Clay  lenses  and  pockets  are 
mixed  with  the  ore.  The  ore  is  loose  enough  to  be  broken  down  w  ith 
a  pick,  and  at  some  places  a  fact1  of  ore  may  be  worked  down  by 
gravity  directly  into  tram  cars.  One  washer  is  employed  here,  clean- 
ing up  400  to  500  tons  of  ore  a  week,  most  of  which  is  shipped  to  the 
two  furnaces  at  Chattanooga.  It  is  understood  that  this  ore  the 
only  product  of  the  district  that  is  sold  on  the  market — commanded 
in  the  summer  of  1906  $1.40  per  ton  at  the  mines,  the  rejecting  point] 
being  a  minimum  of  44  per  cent  metallic  iron. 
Fluxing  material. — The  Bangor  beds  in  this  district  contain  an 
abundance^  good  limestone  suitable  for  smelling  purposes.  The 
Sheffield  Coal  and  Iron  Company  operates  a  quarry  and  crusher  near 
the  ore  washer  in  see.  36  The  stone  is  taken  from  that  horizon  oq 
the  Bangor  limestone  which  commonly  underlies  the  ore  deposits  and 
comprises  oolitic  and  fossil iferous  strata.  The  composition  of  the! 
rock  as  used  in  the  furnaces  at  Sheffield  is  shown  in  the  table  below 
(column  I).  Limestone  for  the  Sheffield  furnaces  is  also  obtained 
from  the  extensive  Fossick  quarries  in  the  W.  j  sec.  10,  T.  7  S.,  R.  12 
W.,  2\  miles  west  of  Darlington.  Here  the  rock  is  a  uniformly  fine- 
grained, white,  oolitic  limestone  about  27  feet  thick.  It  lies  prac- 
tically flat  in  thick  beds  and  is  underlain  and  overlain  by  chert! 
strata.  This  limestone  is  also  quarried  largely  for  building  and 
monumental  purposes,  blocks  weighing  25  tons  or  more  having  been 
cut  out  by  means  of  channeling  machines.  From  10  to  12  cars  a 
day  <>f  fluxing  stone  and  3  to  4  cars  a  week  of  sawed  stone  are  shipped 
from  this  place. 
An  analysis  of  the  Fossick  quarry  rock,  made  at  the  United  States 
Arsenal,  Watertown,  Mass.,a  is  shown  below  in  column  II. 
Analyses  of  Bangor  fluxing  stont . 
Constil  uent. 
I.               II. 
Silica  (Si02) 
} 
2                      .  .50 
Alumina  (AI2O3) 
1.  40 
54 
1.45 
:.4.  20 
1.23 
■12.  61 
Ferric  oxide  1  1  *-<  1          
Lime  (CaO) 
Magnesia  (MgO) 
Carbon  dioxide  (CO2) 
aMcCalley,  Henry,  Report  on  the  valley  regions  of  Alabama,  Alabama  Geol.  Si 
r\ 
ey,  L89I 
.  p.  197. 
