Development of pressed sulfide powder tablets for in situ sulfur and lead isotope measurement using LA-MC-ICP-MS

• Published in: International journal of mass spectrometry 2017-10, Vol.421, p.255-262
• Main Authors: Bao, Zhian, Chen, Lu, Zong, Chunlei, Yuan, Honglin, Chen, Kaiyun, Dai, Mengning
• Format: Article
• Language: English
• Subjects: Accuracy; Homogeneity; LA-MC-ICP-MS; Lead isotope; Sulfur isotope
• ISSN: 1387-3806; 1873-2798
• DOI: 10.1016/j.ijms.2017.07.015

[Display omitted] •A new method was used to synthesize pressed sulfide powder tablets (PSPTs) with homogeneous lead and sulfur isotope compositions on a micro-scale.•Three PSPTs (pyrite, chalcopyrite, and sphalerite) were applied to verify the reliability and robustness of our analytical protocol.•PSPTs with different material matrices were suitable to service as external standards which were used for tandem LA-MC-ICP-MS analysis. Controlling the accuracy and precision of sulfur and lead isotopic compositions in natural sulfide minerals requires the use of well-characterized reference materials with matrices similar to those of the unknown samples being analyzed. However, it is often a challenge to prepare natural or synthetic reference materials with homogeneous isotope compositions on a micro-scale. Herein, we report a novel method to synthesize homogeneous sulfide reference materials in the form of nano-particulate pressed sulfide powder tablets (PSPTs). Non-matrix-matched external calibration was used to obtain accurate and precise lead isotopic ratios, while mass bias was corrected using a standard-sample bracketing method and a thallium standard solution doping process. In situ analysis of lead isotopic ratios of PSPTs using laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) yielded good external precisions of