3.2.2. XRD of the G60 after Treatment at a Temperature

Sample G60 is selected to study the effect of temperature on the crystalline phases formed by heat-treating. Sample G60 is heat-treated at a temperature of 950 ◦C for 2 h and also at 1000 ◦C for two hours (Figure 4). It is shown that after its heat treatment at 950 ◦C for 2 h, anorthite (CaAl2Si2O8) (JCPDS No.18-1202) is formed with the following lines 3.173, 4.013, 2.875, and 2.138Å. When the temperature is raised to 1000 ◦C, the mineral diopside is formed with anorthite, and this shows that the anorthite phase is formed before the diopside phase and at low temperatures. This agrees with Juan Qin et al. [30].
