In Situ High Temperature X-ray Diffraction Research for Kunlun Green Jade

摘要

The jasper from Kunlun Mountain in Qinghai is analyzed with the method of situ high temperature X-ray diffraction(HT-XRD) analysis, which gives the result that the chemical formula of its main composition is Ca2Mg5[Si4O11]2(OH)2 at room temperature, proving to be Tremolite, still mixed with a spot of Dolomite and Talc. By analyzing the diffraction data, it is found that at 1150°C for the jasper's main composition phase transition occurs. This phase transition is that the Ca-Mg pyroxene forms because of the Tremolite being affected by products of the thermal decomposition of Dolomite and Talc.