314  CONTRIBUTIONS    TO   ECONOMIC    GEOLOGY,   L906,   PART    I. 
In  the  following  table  of  analyses  and  tests  the  kaolins  of  Georgia 
are  compared  with  the  best  known  domestic  and  foreign  kaolins. 
The  Georgia,  South  Carolina,  and  Florida  clays  are  sedimentary  in 
origin;  the  remaining  five  are  residual  clays. 
Table  showing  composition  and  comparative  tests 
of  cla\ 
s. 
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
Silica 
Alumina 
i:.:;7 
38.06 
.  63 
Trace. 
Trace. 
.26 
.60 
L.37 
a  11. 83 
.  It 
!.  19 
w  bite 
Low. 
91.33 
44.76 
38.41 
.63 
.20 
.09 
.35 
.09 
L.37 
1  1.  16 
L.22 
L.36 
3,100°F.+ 
White. 
;,ii  to  55 
1            5% 
l          i.v. 
45.39 
39.19 
.45 
.51 
.29 
}      .83 
1 
1  l.nl 
45.02 
38.98 
.77 
.03 
.07 
(       .26 
\      .55 
.85 
13.58 
45.70 
10.61 
L.39 
.45 
.09 
|          2. 82 
16.24 
36.25 
L.64 
.  L9 
.32 
2.  53 
46.87 
38.00 
.89 
Trace. 
.35 
1.22 
48.26 
37.64 
.  Hi 
.06 
Trace. 
L.56 
47.50 
37.40 
.80 
Lime 
Magnesia 
Potash 
Soda 
Trace 
1.10 
Water 
8.  98 
.  35 
4.75 
2,700°  F.+ 
white. 
20 
i 
I           r. 
96.81 
L3.53 
12.  70 
L2.02 
12.48 
Fluxes 
2.08 
L.68 
1.70 
2    16 
2.08 
1.90 
b'27+ 
Nearly 
white. 
65 
}     15% 
w  Liite. 
L3 
l«"  , 
96.95 
Air  shrinkage 
99.00 
^Contains  0.04  percenl  sulphur. 
l.  Kaolin  from  Gibson,  Ga.,  unwashed. 
2  Kaolin  from  Dry  Branch,  Ga.,  unwashed. 
:  Ball  claj  from  Edgar,  Fla.,  washed. 
i  Kaolin  from  Aiken,  S.  C,  unwashed. 
5  Kaolin  from  Webster,  \.  C.,  washed. 
ij.  Kaolin  from  BrandywineSumm.it,  Pa.,  washed. 
7.  Zettlitz,  Bohemia,  washed. 
8.  Cornwall,  England,  washed. 
9  Wesl  Cornwall,  Conn.,  washed. 
*>Cone. 
CLAY   MINING. 
Clay  mining  is  carried  on  actively  ;it  two  localities,  Dry  Branch  and 
Hephzibah,  and  small  amounts  of  clay  are  mined  at  Griswoldville, 
Lewiston,  and  Carrs  Station.  No  washing  plants  are  installed  at  any 
of  those  places,  the  day  being  shipped  in  the  crude  state.  At  Dry 
branch  and  Hephzibah  the  kaolin  is  placed  in  long  drying  sheds,  and 
after  about  t  hree  weeks  of  air  drying  is  ground  into  flour  or  into  small 
lumps,  and  is  shipped  in  sacks,  each  holding  about  200  pounds,  and  in 
wooden  casks  each  holding  approximately  a  long  ton.  The  over- 
burden is  removed  by  hand  labor  and  by  steam  shovels,  and  mining  is 
done  by  the  open-pit  method.  Both  the  overburden  and  the  clay  are 
soft,  and  no  blasting  is  required.  The  installation  of  washing  plants 
and  steam  shovels  will  materially  increase  the  profits  in  mining  these 
clays,  for  a  product  of  greater  purity  and  uniformity  can  thereby  be 
procured,  all  the  material  that  now  forms  waste  can  be  utilized,  and 
larger  quantities  of  clay  can  be  handled.  The  enormous  profits  that 
may  accrue  from  some  other  forms  of  mining  are  not  to  be  expected  in 
clay  mining:  but  by  properly  handling  the  clay  and  by  economical 
management  a  reasonable  profit  on  an  investment  can  be  obtained. 
