S-Fe-Cu isotope systems are powerful tracers for revealing geochemical processes. However, the microanalysis of S-Fe-Cu isotopes is critically limited by the lack of suitable reference materials. Herein, we present three potential reference materials Ll-Cpy (chalcopyrite), Ll-Po (pyrrhotite) and Ll-Sp (sphalerite) for in situ S-Fe-Cu isotope measurements. Numerous in situ S-Fe-Cu isotope measurements were performed over two years to assess isotopic homogeneity. The bulk S isotopic compositions were determined independently in seven laboratories by isotope ratio mass spectrometry (IRMS); the preferred δ³⁴S_V-CDT for Ll-Cpy, Ll-Po, Ll-Sp are 6.13 ± 0.37‰ (2s), 6.42 ± 0.37‰ (2s) and 6.28 ± 0.38‰ (2s), respectively. The bulk Fe isotope ratios in Fe-bearing Ll-Cpy and Ll-Po were determined using solution nebulisation multi-collector inductively coupled plasma-mass spectrometry, and the obtained δ⁵⁶Fe_IRMM-014 values are 0.57 ± 0.07‰ (2s) and -0.62 ± 0.07‰ (2s), respectively. The mean bulk δ⁶⁵Cu_{NIST SRM 976} value of Ll-Cpy is 0.57 ± 0.06‰ (2s). All the bulk values are in good agreement with the long-term statistical results of laser ablation-MC-ICP-MS and proposed as the recommended values. These sulfides are well characterised and isotopically homogeneous (at 30–40 μm spatial resolution), and can be used as potential calibration materials for in situ S-Fe-Cu isotope measurements.

中文翻译：

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用于微束 S-Fe-Cu 同位素测量的新型潜在硫化物参考材料

S-Fe-Cu 同位素系统是揭示地球化学过程的强大示踪剂。然而，S-Fe-Cu同位素的微量分析由于缺乏合适的参考材料而受到严重限制。在此，我们提出了三种用于原位S-Fe-Cu 同位素测量的潜在参考材料 Ll-Cpy（黄铜矿）、Ll-Po（磁黄铁矿）和 Ll-Sp（闪锌矿） 。两年来进行了大量原位S-Fe-Cu 同位素测量，以评估同位素均匀性。七个实验室通过同位素比质谱 (IRMS) 独立测定了大部分硫同位素组成；Ll-Cpy、Ll-Po、Ll-Sp 的优选 δ ³⁴ S _{V-CDT分别为 6.13 ± 0.37 ‰ (2} s )、6.42 ± 0.37 ‰ (2 s ) 和 6.28 ± 0.38 ‰ (2 s )。采用溶液雾化多接收器电感耦合等离子体质谱法测定了含Fe的Ll-Cpy和Ll-Po中的大量Fe同位素比，得到的δ ⁵⁶ Fe _IRMM-014值为0.57 ± 0.07‰ (2 s )和-0.62±0.07‰（2秒），分别。 Ll-Cpy 的平均体积 δ ⁶⁵ Cu _{NIST SRM 976}值为 0.57 ± 0.06‰ (2 s )。所有体积值与激光烧蚀-MC-ICP-MS 的长期统计结果非常吻合，并建议作为推荐值。这些硫化物具有良好的特征和同位素均质性（空间分辨率为 30-40 μm），可用作原位S-Fe-Cu 同位素测量的潜在校准材料。