68 GEOLOGY AND MINERAL RESOURCES OF MISSISSIPPI. 
can be crumbled between the fingers. The sandstone belongs to the Grand Gulf formation. 
It is underlain by calcareous beds. The thickness of the clay bed could not be determined. 
The following analysis shows the composition of this clay: 
Analysis ofVicksburg clay, Warren County. 
[By W. F. Band, State chemist.] 
Silica (SiOs) f)8. 50 
Alumina. (AI2O3) 19. 04 
Ferric oxide ( Fe 2 < h) 1. 93 
Lime (CaO) 1. 48 
Magnesia ( MgO) 1. 66 
Sulphur trioxide (SO3) Trace. 
Moisture 3.19 
Loss on ignition 8. 2$ 
94.06 
Tdij/orsville clay. — Five miles north of Taylorsville, on property belonging to J. S.Eaton 
and brother, on Fisher Creek, the typical Grand Gulf clay of the southeastern area out- 
crops. It is a dark-gray clay containing a large amount of carbonaceous matter, which is 
driven off under a high heat and the burned clay is of a buff color. A sample of the clay wai 
sent by J. S. Eaton to the St. Louis Fire Brick Company to be tested for fire brick. It was 
found, however, that the clay, when used alone, cracked too much in burning. The fol- 
lowing analysis has been made of this clay: 
Analysis of Taylorsville clay, Smith County. 
[By W. F. Hand, State chemist.J 
Silica (Si0 2 ) 71. 21 
Alumina (AI2O3) Hi. 78 
Ferric oxide (Fe203) 3. 3d 
Lime (CaO) lj 
Magnesia (MgO) 41 
Sulphur trioxide (SO3) 'trace. 
Moisture 1. a 
Loss on ignition 6. 6(1 
99. ad 
Laurel brick day. At Laurel, Jones County, the Lafayette is very thin and in place! 
entirely washed away. The underlying Grand Gulf clay is dark gray to bluish in color and 
is well adapted to making common brick. The clay is high in silica, but contains sufficiefl 
alumina to bond it. It is claimed by the manager of the Laurel Brick Company that 1! is 
almost impossible to burn the clay too hard with wood fuel. The amount of iron in the clay 
causes the brick to burn to a deep-red color. The following is an analysis of the Laurel clay: 
Analysis of Laurel brick clay, Jones County. 
[By W. F. Hand, State chemist.] 
Silica (Si0 2 ) 84. 8d 
Alumina (AI2O3) 5. a 
Ferric oxide (Fe20 3 ) •'<• 96 
Lime (CaO) 23 
Magnesia (MgO) 45 
Sulphur trioxide (SO3) Traces 
Moisture 1.2SJ 
Loss on ignition 3. 66 
'.to. 66 
LAFAYETTE CLAYS (EARLY QUATERNARY) . 
The prevailing materials of the Lafayette formation are gravels and sand, but occasionally 
small, irregular deposits of clay are embedded in the coarse sand. The clay when present is 
usually greatly discolored by the presence of iron oxide, though in some places, as at MortonJ 
Scott County, bodies of snow-white clay are found with scarcely a trace of iron. 
