Study on the Mineralogical Characteristics of Cinnabar Jade by X-ray Powder Diffraction-Laser Raman Spectroscopy-Electron Probe from Xunyang, Shan'xi Province

In recent years, due to the similar appearance of Chicken-blood stone, red cinnabar jade has been a research concern of mineral composition, lithology and other related aspects in Jilin, Guizhou, Qinghai and other places. To investigate this further, mineralogical and gemological research has been conducted on cinnabar jade in Xunyang, Shaanxi Province, by means of normal gem conventional determination, Polarizing Microscope, X-ray Powder Diffraction (XRD), Laser Raman Spectrometer (LRS) and Electron Probe (EP). The main mineral compositions of the samples are quartz and cinnabar, with minor calcite, dolomite, barite and pyrite. The color of cinnabars becomes darker with the increase of iron content. The mineral textures are mainly clastic, granular and interpenetration metasomatic. Both the red cinnabar jade samples and bloodstone contain cinnabar, leading to their similarity in appearance. Moreover, there are obvious differences in deposit genesis and mineral composition between them. Cinnabar jade in Xunyang belongs to sedimentary-hydrothermal-strongly alteration ore deposit. The matrix of the samples is quartz, and the phenocryst is cinnabar. Chicken-blood stone of Changhua in Zhejiang Province and Balin in Mongolia Province are found in secondary fractures of Mesozoic metasomatic acidic volcanic rocks and the matrix minerals are dickite, kaolinite and pyrophyllite, with the same phenocryst of cinnabar as the samples used in this study.