X-ray diffractrometry (XRD) was the tool to characterize crystalline of product. Figure 3 show XRD pattern of B-dicalcium silicate by microwave method at 700 W with calcination at 800 C for 1 hr. The phases detected by XRD were polycrystalline as silica (JCPDS file number 04-0733) ,calciumcarbonate (JCPDS file number 04-0733) and lime (JCPDS file number 04-0733). While calcination at 1000 C (Figure 4), the diffraction patterns were well with B-dicalcium silicate and reduction of calciumcarbonate due to calcium carbonate decomposition at 1000 C following equation (1).