IX. A, 1 West and Cox: Philippine Cement Raw Materials 101 



Table XXII. — Standard slurry mixture of the Sandusky Portland 



Cement Company. 



Constituent. 



Per cent. 



Silica (SiOj) 



13.51 



Alumina (AUOa) 



3.50 



Iron oxide (Fe.Os) 



1.43 



Alumina plus iron oxide (RjOs) 



4.93 



Calcium oxide (CaO) 



40.84 



Magnesia (MgO) 



0.75 



Sulphuric anhydride (SO3) 



1.43 



Loss on ignition 



37.50 



SiOj 



2.81 



RjOs 





CaO 



2.21 



SiO^+RsO, 



Cementation index 



1.02 



This approximately corresponds to the composition of actual 

 mixture given by Eckel, ^* which lie approximately within the 

 limits indicated by the following analyses : 



Table XXIII. — Composition 



of actual cement mixt 







(1) 



(2) 



Constituent. 





Per cent. 



Silica (SiOj) 





14.94 



12.92 



Alumina (AI2O3) 





2.66 



4.83 



Iron oxide (Fe.Os) 





1.10 



1.77 



Alumina plus iron oxide (R2O3) 



3.66 



6.60 



Calcium oxide (CaO) 





42.34 



42.30 



Magnesia (MgO) 





2.21 



2.08 



Carbon dioxide (CO2) 





35.68 



35.49 



Water 









SiO= 

 R=0, 





4.08 



1.96 



CaO 





2.28 



2 17 



SiOj+R^O. 



£«>X • 



Cementation index 





1.00 



0.945 



It was our intention to extend and expand this investigation, 

 but the pressure of other work and the departure of one of us on 

 an extended leave of absence induce us to present the results now 

 completed. 



" Cements, Limes, and Plasters. John Wiley and Sons, New York (1909), 

 394. 



