102 '^he Philippine Journal of Science i9u 



SUMMARY 



The silica to alumina (plus iron oxide) ratio, the lime to silica, 

 alumina, and iron oxide ratio, and the cementation index of the 

 mixtures of Philippine cement raw materials which we have used 

 are entirely within the limits of technical mixtures which have 

 successfully been used elsewhere. The cement produced from 

 these materials was sound and of high specific gravity and tensile 

 strength. The results which we have obtained show that the 

 materials which we have investigated are well adapted to the 

 manufacture of Portland cement. 



