Iron, Copper and Zinc Isotopic Compositions of Basaltic Standard Reference Materials

Fe, Cu and Zn isotopic compositions of 3 basaltic standard reference materials of BCR-2, BIR-1a and GBW 07105 were reported in this paper. The basaltic samples were digested with HNO₃-HF mixed acids. Anion exchange resin AGMP-1 was used in the separation of Fe, Cu and Zn from other elements. Fe, Cu and Zn isotopic ratios were determined by Multiple Collector-Inductively Coupled Plasma-Mass Spectrometry (MC-ICPMS), and isotopic mass fractionation was calibrated by Standard-Sample bracketing. The Fe, Cu and Zn isotopic composition of 3 basaltic standard reference materials (at 95% confidence level) were as follows: δ⁵⁶Fe_{BCR-2-IRMM014}=0.070‰±0.018‰ (2SD), δ⁶⁵Cu _BCR-2-SRM976=0.16‰±0.04‰ (2SD), δ⁶⁶Zn_{BCR-2-IRMM3702}=-0.072‰±0.020‰ (2SD); δ⁵⁶Fe_{BIR-1a-IRMM014} =0.044‰±0.026‰ (2SD), δ⁶⁵Cu _{BIR-1a -SRM976}=0.027‰±0.019‰ (2SD), δ⁶⁶Zn_{BIR-1a-IRMM3702}=0.085‰±0.032‰(2SD); δ⁵⁶Fe_{GBW 07105-IRMM014}=0.126‰±0.039‰(2SD), δ⁶⁵Cu_{GBW 07105-SRM976}=0.12‰±0.01‰ (2SD), δ⁶⁶Zn_{GBW 07105-IRMM3702}=0.22‰±0.03‰(2SD). These data were in good agreement with published data within uncertainties. The Fe, Cu and Zn isotopic data of basaltic reference materials provide a new standard for relevant research, and a method for evaluation of the quality of the whole process of sample preparation and isotope measurement.