The δ 114/110 Cd values of thirty-four environmental and geological reference materials, including rocks, sediments, soils and biological samples, were determined on a Neptune Plus MC-ICP-MS instrument using a 111 Cd-113 Cd double spike technique. An intermediate measurement precision of better than AE 0.074‰ (2s) was achieved with different reference materials (RMs) of highly variable matrices and Cd contents. The uncertainty of δ 114/110 Cd values was assessed by calculating the 95% confidence interval of the results from this study and the literature using Student's t-test. Our measurements of nine previously analysed RMs yielded δ 114/110 Cd values that were indistinguishable from previous results. New reference values for the thirty-four geological and biological RMs are reported here. The comprehensive data set for these RMs provides guidelines for quality assurance and inter-laboratory comparison for Cd isotope determination. The large range of δ 114/110 Cd values in rock (-0.001 to +0.287‰) and biological RMs (-0.806 to +0.142‰) suggests that Cd isotope ratio measurement results are a useful tool to study biogeochemical processes.

The Middle-Lower Yangtze Region (MLYR) is one of the most important metallogenic belts in China that hosts numerous Cu-Fe-Au-S deposits. The Hucunnan deposit in the central part of MLYR is a newly discovered porphyry-skarn-type copper-molybdenum deposit during recent drilling exploration. Laser ablation ICP-MS analysis carried out in this study yields U-Pb isotopic ages of 137.5 ± 1.2 Ma for the Cu-Mo bearing granodiorite rock and 125.0 ± 1.5 Ma for the Cu-bearing quartz diorites. The Re-Os isotopic dating of seven molybdenite samples gave an isochron age of 139.5 ± 1.1 Ma, suggesting a syn-magma mineralization of molybdenite in the Hucunnan deposit. Since porphyry-type molybdenum deposits are rare in central MLYR, the discovery of the Hucunnan deposit suggests possible molybdenite mineralizations in the deep places of the Cu-Mo bearing granitoids. In addition, the U-Pb isotopic age of 125 Ma for the Cu-bearing quartz diorites implies a new Cu mineralization period for the MLYR that was rarely reported by previous studies.

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