Abstract: Electron probe micro-analyser (EPMA) has been used to analyze the content and existence form of element C among the thin slices of metallic ore from Dongshengmiao sulfide polymetallic deposit.The results showed that different content of carbon are detected from metallic minerals such as sphalerite,pyrrhotite,pyrite and chalcopyrite,but the there is no element C existed in galena which may be related to the nature of Pb mineralization.In addition,dolomite,magnesite and the compound of hybrid materials of carbonate and hydroxide of Fe are detected in the gangue minerals around these metallic minerals,and in most cases,element C is existed in the gangue minerals in the form of carbonate.The high carbon content of material is detected in the surrounding junction area of different metallic minerals and the metallic minerals inclusions (the content of C more than 75%),which is speculated to be the organic matter combing with the characteristics of the sulfide polymetallic deposit.The contrast analysis on test results indicated that the organic matter has a close relationship with metallic minerals and participates in the mineralizing process from the microcosmic view.

Key words: Organic matter, Investigation of mineralization, Dongshengmiao deposit, Electron probe micro-analyser