WILCOX CLAYS. 57 
Analysis of Mad in clay, Benton County. 
[By \V. F. Band, State chemist.] 
Silica (SiOa) 64. 86 
Alumina (AI2O3) 20. 70 
Ferric oxide (Fe 2 3 ) 4. 19 
Lime (CaO) <. 69 
Magnesia (MgO) 59 
Sulphur trioxide (S0 3 ) Trace. 
Moisture 62 
Loss on ignition 7. 02 
Parham clay. — A very fat white clay occurs in the NW. \ sec. 36, T. 1 S., R. 1 E., Benton 
County. It is free from sand and burns to a rich cream color. It occurs in a large lens-shaped 
body, 4 feet thick, and is uncovered for 100 yeards along a branch. When dry the clay has 
a tendency to break up into large rectangular blocks. Fossil leaf impressions are abun- 
dant. This clay has been used by the Grand Junction Pottery Company and found to be 
excellent for making common stoneware. Below is an analysis of the Parham clay: 
Analysis of Parham clay, Benton County. 
[By W. F. Hand, State chemist.] 
Silica (Si0 2 ) 59. 02 
Alumina (AI2O3) 25. 78 
Ferric oxide (Fe 2 3 ) 3. 25 
Lime (CaO) 47 
Magnesia (MgO) 24 
Sulphur trioxide (SO3) .- 42 
Moisture 1. 09 
Loss on ignition 8. 37 
98.64 
Umbaryer clay. — In sec. 2, T. 2 S., R. 2 E., ayellow, lean, sandy clay occurs in the stratified 
Wilcox sands. The clay here is entirely below the Lafayette and is made up of thin laminae 
of clays intermingled with more or loss fine sand. It burns to a rich buff color. As in the 
other places mentioned above the clay is present in a large number of gullies where the sur- 
face soil and Lafayette have been washed away. An analysis of this clay is given below: 
Analysis of Umbaryer clay, Benton County. 
[By W. F. Hand, State chemist.] 
Silica (SIO j) 75. 78 
Alumina (AI2O3) 14. 11 
Ferric oxide (Fe 2 3 ) 3. 56 
Lime (CaO) 54 
Magnesia (MgO) 52 
Moisture : 23 
Loss on ignition 4.81 
99. 55 
Boughton clay. — A gray clay with pink streaks through it occurs in the Wilcox strata in (he 
NW. I sec. 34, T. 1 S., R. 2 E., Benton County. It is free from sand and highly plastic. The 
following is an analysis of this clay : 
Analysis of Boughton clay, Benton County. 
[By W. F. Hand, State chemist.] 
Silica (SiO 2) 56. 32 
Alumina (AI2O3) 28. 60 
Ferric oxide (Fe 2 3 ) 2. 60 
Lime (CaO) 45 
Magnesia (MgO) 20 
Sulphur trioxide (SO s ) 32 
Moisture 98 
Loss on ignition - 8. 89 
98.36 
