OKLAHOMA ACADEMY OF SCIENCE 99 



terial and are found quite abundantly strewn over slopes. 



The phospate rock is much like other smooth coprolite-like 

 nodules of limestone found in the same region, with which they are 

 ■very likely to be confused. The preponderant shapes of the nodules 

 collected, were globular, ovoid or elliptically discoid though it is 

 recognized that these forms probably result from chipping, weather- 

 ing, and water rolling, of fragments of veins to be described later. 



The material of which the nodules are made is extremely fine 

 grained, in most cases so much so that the mineral particles can 

 not be distinguished. However, the association and colors lead 

 to the conc'-usion that the following minerals are present : limonite 

 (yellow), hematite (red), finely divided quartz, aluminum silicates 

 of the nature of kaolinite, pyrolusite and other oxides of manganese, 

 and minerals that account for the calcium, phosphate and fluorine 

 shown by the analysis to exist. 



The chemical composition of the phosphate from an analysis 

 made by the writer is as follows : 

 SiO., 



Ai.,b., 



Fe'O^! 



MgO" - 



CaO 



Na..O : . 



K.,0 



h;;o- , 



H^Ox, ) 



)_-___ 2.90 



Organic ]\Iat'cr ) 



TiO., 



CO,; 



p.,6, 



so/ 



F " 



MnO 



Total 102.516% 



Less O equivalent to F 1.810% 



Total (Corrected) 100.706% 



From the analysis, it is evident that the material is of commer- 

 cial grade since 50.00 per cent of B.P.L. (Bone, phosphate of lime) 

 content constitutes a m.arketable rock and is so c[uoted in the 

 renorts. 



