Study on Modes of Occurrence of Gold for Shuiyindong Gold Bearing Pyrite in Guizhou Province

Topographic observation and composition determination for Shuiyindong pyrite in Guizhou Province were conducted by making use of scanning electron microscope and electron probe.The results show pyrite have multifarious morphology such as strawberry hemangioma,cube,pentagonal dodecahedron and colloidal,etc,which pyrite of pentagonal dodecahedron and colloidal contain gold and indicate some relationship with the content of arsenic.Discussing the situation of gold coming into pyrite lattice with the using of quantum chemistry calculation and the dense packing powder theory,the phenomenon of gold coming into lattice in the form of Au+and replacing S position more easily than Fe position was discovered.It is effortless for Au+entering lattice,when pyrite contain arsenic,but it doesn't mean gold content is directly proportional to arsenic content.With a detection limit,while there is more arsenic,there is more arsenic,but without the arsenic limit,gold is not so easily to enter into the lattice as the former case.