PHILIPPINE RAW CEMENT MATERIALS. 



Table V. — Analyses. 

 [The numbers give percentages.] 



219 



Constituent. 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



Silica (SiOo) 



Alumina (AlaOj)" 



Iron oxide (FeaOa)' 



Calcium oxide (CaO) — 



Magnesia (MgO) 



Alkalies (KoO+NaoO). 

 Loss on ignition 

 Water (H.O) below 

 110°C 



60.17 

 22.65 

 4.66 

 0.31 



1.85 



6.35 



w 



43.38 

 29.44 

 0.48 

 9.50 

 0.61 

 1.66 

 10.75 



6.30 



53.35 

 24.11 

 9.03 

 0.80 

 2.22 



44.35 

 20.26 



4.64 

 11.37 



2.59 



29.00 



11.38 

 5.35 



26.25 

 0.65 

 1.98 



23.00 



3.84 



24.02 

 7.49 

 2,00 



33.88 

 2.12 



0.38 



1 0. 18 



55. 62 

 0.00 



8.72 



14.30 



(«) 



28.25 



43.50 

 0.17 





"Includes possible titanium oxide (TiOo). 

 ^ Total iron determined as ferric oxide. 

 •= Included under loss on ignition. 



These materials may be combined, according to the method of cal- 

 culation outlined under the jDreceding head. If clay numl^er 1 is com- 

 bined with limestone number 7, the formula would require 3.28 parts 

 of limestone to every part of clay and the results would be as follows : 



Table VI. 



IThe numbers give parts of tbe materials by weight.] 





Total. 



Individual constituents. 



Silica 

 (SiO.). 



Alu- 

 mina 

 (ALOa) 



Iron 

 oxide 

 (FeoO;,) 



Cal- 

 cium 

 oxide 

 (CaO). 



Mag- 

 nesia 

 (MgO). 



1 



Volatile 



(CO,, 



H,0, 



etc.). 



Clay (No. 1) 



100 

 333.5 



60.17 

 1.27 



22.65 

 0.60 



4.66 



0.30 

 185.49 



1.85 



6.35 ; 



143.25 



Limestone (No. 7) 



Unburned 



Volatile 



433.5 

 152.0 



61.44 



23.25 



4.66 



18,5.80 



1.85 



151. 99 





281.5 



21.83 



8.26 



1,65 



66.00 



0.66 









It will be noticed from the parts by weight (percentage composition) 

 of the burned product that the content of lime is higher than that of 

 the average Portland cement. The results of the formula represent the 

 maximum of lime which a cement can carry, if it were manufactured 

 under ideal conditions. In actual practice these are seldom met with 

 and it is therefore necessary to carry the lime lower than that indicated 

 by the formula. Furthermore, a cement which has a comparatively 

 low everburning temperature is always burned at the lowest possible 

 point and at this temperature will usually not carrj' the maximum quan- 



85320— —4 



