66 GEOLOGY AND MINERAL RESOURCES OF MISSISSIPPI. 
Winston County stoneware clay. — On the old Eiland place, in sec. 16, T. 15N.,R. 13 W.,Wirs 
ston County, in a deep gully along the public road, is an outcrop of clay, which is being us < 
by the Webster and Joplin stoneware potteries for making common stoneware. The clay a 
pink with streaks of white, resembling castile soap. Like the Parham clay, when air dried, t 
breaks up into more or less rectangular blocks. It occurs in a lenticular mass 2k feet thick 
in the bed of clayey, indurated sand containing mica. The clay burns to a rich buff color. 
The following analysis has been made of this clay: 
Analysis of Winston County stoneware clay. 
[By W. F. Hand, State chemi 1.1 
Silica (Si0 2 ) . r >7. 37 
Alumina ( A1 2 8 ) 29. 87 
Ferric oxide (Fc 2 () 3 ) 1. 88 
Lime (CaO) 71 
Magnesia (MgO) .14 
Sulphur t rioxide (SC) 3 ) Trace] 
Moisture .81 
Loss on ignition 8. 53 
•19.31 
Webster County stoneware clay. — At Cumberland, Webster County, is a small stoneware 
factory, which secures its clay from a pit on the side of the public road on land belonging to 
B. F. Sanders, in sec. 22, T. 20 N.,R. 11 W. The day has a chocolate color, due to the carbo- . 
naceous mat ter, and duos not require t lie admixture of other clays for making stoneware. It 
burns to almost a snow white. It occurs in stratified planes overlain by a less pure sandy 
clay. The following is an analysis of this clay: 
Analysis of Webster County stoneware clay. 
[By W. V. Eland, State chemist.] 
Silica (SiOj) "9. 82 
Alumina (A1 2 3 ) 27. 19 
Ferric oxide (Fe 2 3 ) 1. 26 
Lime (CaO) 49 
Magnesia (MgO) 37 
Sulphur t rioxide (S0 3 ) 31 
Moisture 1. 47 
Loss on ignition 9. 24 
100. 15 
CLAYS OF THE JACKSON FORMATION (UPPER EOCENE). 
Very little at lent ion has been paid to the vast deposits of calcareous clays of the Jackson 
formation. The importance of these clays from an economic standpoint is yet to be deter- 
mined. Some of them contain a large amount of lime carbonate, but clay with as high as 20 
per cent of lime, if this is in a finely disseminated condition, can be used in making common 
brick, roof tiling, and in some cases stoneware and terra cotta. 
The following analyses and notes on the Jackson clays were made by Dr. E. W. IIilgard:» 
Underclay of gypseous prairie, from see. 12, T. 6, R. 3 E. Depth, 3 to 7 feet (as far as visible) I, How 
the surface. A greenish-gray heavy clay with numerous small white specks (of gypsum) and som 
round concretions of iron ore. 
Analysis of clay from sec. 12, T. 6, R. 4 E. 
: 
Silica (Si0 2 ) (17.027 
Alrmina (A1 2 3 ) 10. 751 
Ferric oxide (Fe 2 3 ) 4. 344 
Lime (CaO) 5. 695 
Magnesia (MgO) 1. 233 
a Geology and Agriculture of Mississippi, 1860, pp. 337. 340 341. 
