Li Jiuling,Feng Daming,Qi Feng and Zhang Guilan Institute of Mineral Deposits,Chinese Academy of Geological Sciences,Beijing Beijing U niversity of Science and Engineering,Beijing Fei Zhenbi
基金项目:
This study was supported by Grant 4880158 from the National Natural Science Foundation of China,Category A Project of Scientific Activities of Returned Personnel Sent Abroad for Advanced Study by Non-educational Institutions of the Ministry of Personnel
摘 要:
Through a study, particularly an X-ray photoelectron spectroscopy (XPS or ESCA) analysis, of gold-bearing arsenopyrite and pyrite in Carlin-type gold deposits of Guangxi, China, and hydrothermally synthesized gold-bearing pyrite and marcasite, the authors have found that these minerals contain "invisible gold" whose binding energy is lower than that of native gold (Au°). Therefore they suggest that gold occurs in a negative charge state in these sulphide minerals as it replaces some sulphur and is combined with sulphur with the covalent bond. This paper also preliminarily discusses the possibility of its formation from the chemistry and geochemistry of gold, crystal chemistry of arsenopyrite, pyrite and marcasite and geochemical environment.
The Existence of the Negative Charge of Gold in Sulphide Minerals and Its Formation Mechanism