CEMENT    RESOURCES    OF    CUMBERLAND    GAP    I 
-'• 
i  series  of  heavy-bedded  blue  to  gray  limestor.  - 
250  to  400  feet.     Cherty  beds  occur  at  several  ho: 
K  the  rock  is  fairly  pure  and  low  enough  in  mag     -  ... 
ial  for  Portland  cement  manufacture. 
l. 
Silica  (SiO, 1.40  36       iOc  -. 
Alumi-  
}  1.00  56  0       1.23         .42 
Iron  os  | 
Lime  ^  -  '     .      -" 
slum  oar 
-  - 
n.d. 

..... 
■      . 
shales.     The  shales  required  for  cement 
gic  groups  sures,  the  Pennii  gton  shales  _ 
Chattanooga  shales.     Each  o(  these  formations  is 
three  outcrop  along  the  southeastern  flank  of  Cumb* 
Coal  Measures  outcrop  in  the  Middlesboro  basin  nort        - 
bo  briefly  described  in  geologic  order. 
The  Chattanooga     Devonian)  shale  ioi\-  -  - 
It  consists  of  brittle  black  carbonaceous  shales        -  g  small  percent- 
ages of  pyrite.     Some  beds,  therefore,  contain  too  much  snip:  satisfac- 
tory as  cement  material,  but  the  mass  o(  the  formation  is  good  en,    »hs  s  its  sul- 
phur content   is  concerned.     These  shales  arc  -     idy,  and  : 
often  talis  so  low  that  the  following  ratio  is  obtained: 
S 
All'.' 
While  material  with  this  silica-alumina  ratio  can  be  used  in  cement  manufacture,  the 
shales  next  to  be  considered  would  seem  mon    - 
The  Grainger  formation,  lying  above  the  Chattanooga  shales  and 
varies  from  50  to  L2S  feel  in  thickness.     It  is  eomp  -  gra  sh  shales,  sili- 
ceous enough  on  analysis,  but  with  no  coarse  sandy  beds.     For  th  - 
probably  the  most  satisfactory  as  a  cement  material. 
.I;..:     s  - 
AUnuma  (AUOs) 
Iron  ox 
Lime  carbonate  (CaCO 
-sunn  carbonate    Mj  I 
The  above  analysis  was  made  in  UXM  in  J.  G.  Harding,  of  Wellsti  I                     sample 
of  shale  taken  a  few  feet  below  the  limestone  in  the  M        -       quarry.  It  is  obvio   s 
very  satisfactory  shale  for  use  in  Portland  cement  manutV.  -              sition, 
giving  the  following  ratio: 
Alun  s 
The  Pennington  shale  formation,  which  overlies  the  limestone,  is  here  i  ISO 
feet  thick,     [t  consists  of  beds  of  greenish  shales,  with  alternating  thin   ..     so   -     ds 
