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A systematic study of the phase composition and element occurrence characteristics of tellurides in tellurium-bearing gold deposits will be helpful for the genesis understanding of gold deposits of this type and for prospecting exploration. Tellurides in the Jinqingding gold deposit are too small and are difficult to identify. Previous research lacked the detailed studies of the element distribution characteristics of tellurides. In this study, the types, symbiotic relationship, chemical composition and element distribution characteristics of tellurides in the deposit were analyzed by electron probe using BSE, WDS, EDS and mapping modes. Results show that petzite is closely associated with hessite and intergrowths of these two minerals are common. Au and Ag are unevenly distributed in the intergrowths, and calaverite shows as a bright spot in the scanning map. Tellurium is always likely to combine with Ag to form hessite. With the consumption of Ag, petzite began to appear and Te combined with Au to form calaverite after exhausting Ag in magmatic hydrothermal fluids. The superfluous Au in the hydrothermal fluids at the later stage of mineralization reacted with hessite or petzit to produce unconventional tellurides, finally forming a native gold. The growth of gold-silver minerals follows the sequence, hessite, petzite, calaverite, and Au from early to late. This study provides technical support for the comprehensive utilization of tellurium-bearing gold deposits.

During LA-ICP-MS analysis, the key factor influencing data accuracy of sample analysis is whether the sample can be uniformly delivered from the laser sample chamber to the torch of the ICP-MS.An external container between LA and ICP-MS and a multi-channel rotary sampling cell, which can effectively eliminate the sample position effect during the laser ablation was designed for the study reported in this paper.The pattern of aerosol delivered to ICP-MS is approximately continuous and at the same time, this can greatly improve the stability.Under optimal conditions, using 91500 as external standard, the standard zircons GJ-1, Ple ovice, TEMROA and QH yield U-Pb ages of 604±3 Ma(2δ, MSWD=1.2), 337±1 Ma(2δ, MSWD=1.18), 419±3 Ma(2δ, MSWD=0.15) and 161±1 Ma(2δ, MSWD=0.6), respectively, which agree well with the previously reported ID-TIMS and SHRIMP ages.For the same conditions, using NIST610 as external standard, most trace element results of the glass standards NIST612 and BHVO-2G fall within 10% range of the reference values.The 207Pb/206Pb weighted mean age of zircons from the Tianshan Orogen of Xinjiang is consistent with the previous SHRIMP U-Pb age within uncertainty.This method can effectively reduce the elemental fractionation effects and improve the reliability of the analytical data.