Abstract:

The Jincang mineralized belt is very important in the Yanbian Mesozoic volcanic area. It is related to gold mineralization in the area. In the mineralized belt, there are two types of pyrite: fine veined pyrite and coarse disseminated pyrite. Main elements and trace elements of the two types of pyrite were analyzed. Both types of pyrite are all lower in sulfur and belong to the sulfur depletion type, indicating a forming environment at deep and high temperature. The contents of trace elements in the two types of pyrite are different and are related to different metallogenic epochs. Contents of Au and Ag in the two types of pyrite were low while those of  Cu, Pb, Zn are abnormally high. Among the high temperature element, content of Ni is higher than that of Co, indicating the pyrite formed at high temperature. In pyrite, not only the isomorphous replacement of Fe by Co, Ni , but also S by As, Sb are common. The pyrite in Jincang mineralized belt are not of the typomorphic characteristics of the gold metallogenesis related to volcanic hydrothermal fluids, but of the typomorphic characteristics of copper metallogenesis when compared with pyrite in the typical gold deposits related to volcanic hydrothermal fluids. The geochemical characteristics of pyrite can indicate the formed environment of the minerals and provide prospecting criterion for mineral exploration.

Key words: mineralized belt, pyrite, typomorphic characteristics, prospecting criterion