112 Ferguson and Merwin — The Ternary System. 



Composition wt. v % 

 CaO MgO SiO s 



45 

 46-7 

 44-3 

 44 



5 

 31 



2-8 

 6 



50 

 50-2 

 52-4 

 50 



Temp. 

 °C. 



1476 



1468 

 1490 

 1500 

 1500 

 1510 

 1470 



Time 

 in 

 min. 



10 

 15 

 15 

 15 

 15 

 15 

 15 



Phases present 



Glass 



Glass -f- crystals 



Crystals -f- trace glass? 



Glass 



Trace glass -j- crystals 



Glass -f- trace crystals 



Glass -j- trace crysals 



Table XVII. 



Melting temperatures in the 2CaO.MgO.2SiO., field; melting point of 

 2CaO.Mg0.2Si0 2 1458 ± 5°C. 



Composition wt. t 

 SiO s 



CaO 



35 



39 

 39 



39 



39 



40-33 



41 



41 



MgO 



20 



14 

 15-5 



17 



18 



i4-6e 



13 

 15 



45 



47 

 45-5 



44 



43 



45 



46 



2CaO.MgO.2SiO 



44} 

 i0 2 { 



Time 



in 

 min. 



10 

 10 

 20 

 10 

 10 

 20 

 20 

 20 

 20 

 5 

 10 

 20 

 20 

 20 

 15 

 10 

 10 



Phases present 



Glass 

 Glass -j- 

 Glass -f- 

 Glass -j- 

 Glass 

 Glass -j- 

 Glass 

 Glass 

 Glass -j- 

 Glass 

 Glass -f- 

 Glass 

 Glass -f- 

 Glass 

 Crystals 

 Glass 

 Crystals 



crystals 

 trace crystals 

 crystals 



crystals 



crystals 



crystals 



crystals 



only 



only 



The phase 3Ca0.2Si0 2 is unstable at its melting point 

 and its field is too small to warrant the determination of 

 melting temperatures within it, other than by interpola- 

 tion from the boundaries. 



The phase o2CaO.Si0 2 melts at 2130 ± 10°C and the 

 temperature gradient within its field is so steep that but 

 few melting temperatures were determined. 







Table 



XVIII. 







Melting temper 



•atures 

 < 



within the 2CaO.SiO, 

 x 2CaO.Si0 2 2130 ± 10" 



field. Melting point of 

 3 C. 



Composition wt. % 

 ?aO MgO Si0 2 



Temp. 

 °C. 



Time 



in 

 min. 





Phases present 



48 10 

 45 12 



40 20 



42 

 43 



40 



1547 

 1470 

 1475 

 1546 

 1536 



10 

 15 

 15 

 10 

 10 





Glass -\- trace crystals 



Glass -j- crystals 



Glass 



Glass 



Glass -f- crystals 



