98 



The Philippine Journal of Science 



19U 



Table XVI. — Calculation of volcanic tuff and Binangonan limestone 



cement mixture. 





Total. 



Individual constituents. 



1 



Silica Alumina 

 (SiOa). (Al20s). 



Iron 



oxide 



(Pe20s). 



Lime 

 (CaO). 



Magnesia 

 (MgO). 



Volatlls 



(C02, H»0, 



etc.). 



Numbers give parts of the material by weight. 





317. 50 3. 56 



0.25 

 19.63 



0.22 170.70 



3.78 

 1.70 



137.60 

 9.30 



Tuff . 



100.00 



56.36 



6.97 



4.30 



Unbvimed 



Volatile.. 



417.60 

 146.80 



59.92 



19.78 



7.19 



175.00 



5.48 



146.80 













270. 70 69. 92 



19.78 



7.19 



175.00 



5.48 









Calculated composition in percentage. 



Mixture. 



Clinker 



99.20 



98.77 



14. 35 4. 74 

 22. 13 7. 31 



1.72 

 2.66 



41.92 1.81 

 64. 65 2. 02 



35.16 













The silica to alumina (plus iron oxide) ratio in the mixture is 2.22. 

 The lime to silica, alumina, and iron oxide ratio in the mixture is 2.01. 

 The cementation index of the mixture is 1.06. 



A sample of Binangonan limestone was obtained from the 

 neighborhood of San Guillermo, an abandoned barrio near the 

 town of Teresa in Rizal Province. San Guillermo is situated 

 at an elevation of appro.ximately 200 meters, and is about 5 

 kilometers inland from the town of Darangan on Laguna de 

 Bay. The sample collected was crushed, thoroughly mixed, and 

 ground. The analysis of this sample is given in Table XVII. 



Table XVII. — Analysis of Binangonan limestone from, San Guillermo, Rizal, 



Province, Luzon. 



Constituent. 



Silica (SiO.) 

 Alumina (-'VLOa) 

 Iron oxide (Fe.Os) 

 Lime (CaO) 

 Magnesia (MgO) 

 Volatile matter 



Total 



Per cent. 



2.33 



0.44 

 0.39 



53.40 

 0.74 



42.67 



99.97 



A mixture prepared according to the method of calculation 

 from the formula described above would consist of 1 part of tuff 

 combined with 3.49 parts of Binangonan limestone. Two mix- 

 tures containing 5 and 10 per cent less Binangonan limestone, 



