Application of High-resolution Scanning Electron Microscope and X-ray Energy Dispersive Spectroscope Mapping Technique to Study the Composition and Morphology of Tellurium Minerals

The X-ray Energy Dispersive Spectrometry EDS-Mapping technique can be used to directly observe distribution characteristic of elements in rock sections. The distribution characteristics and elemental assemblage of tellurium(Te) and some other elements(Au and Ag) from the Guilaizhuang gold field in Shandong Province of China were investigated by high resolution Scanning Electron Microscope(SEM) and X-ray Energy Dispersive Spectroscope(EDS) Mapping techniques and are presented in this paper. The morphological characteristics of possible Te minerals, as well as the spatial relationship between Te minerals and other minerals, were also qualitatively determined. The results show that the Te-bearing minerals in the Zhuojiazhuang gold deposit include angular sylvanite and altait, which were disseminated in the space between anhedral quartz and sheet muscovite. The Te-bearing minerals have particle sizes ranging from a few to hundreds of micrometers. Microanalysis of the Te-bearing minerals indicates that the chemical formulae of sylvanite and altaite are Ag0.85Au2.55Te6 and Pb0.52Te0.48, respectively. Sylvanite has an abnormal chemical composition. Through the study, an advanced and practical technique for analyzing the composition and the morphological characteristics of Te minerals and their relationship with wallrock was developed. This study also provides technique support for comprehensive utilization of Te-bearing gold minerals.