TY - RPRT A1 - Vogl, Jochen A1 - Becker, Dorit A1 - Koenig, Maren A1 - Yim, Y.-H. A1 - Lee, K.-S. A1 - Goenaga-Infante, H. A1 - Malinowskiy, D. A1 - Hill, S. A1 - Ren, T. A1 - Wang, J. A1 - Vocke, R. D. A1 - Murphy, K. A1 - Nonose, N. A1 - Rienitz, O. A1 - Noordmann, J. T1 - Certification Report for the Isotopic Reference Materials ERM-AE142 and ERM-EB400 N2 - Lead (Pb) isotope amount ratios are commonly used in applications ranging from archaeology and forensic sciences to terrestrial and extra-terrestrial geochemistry. Despite their utility and frequency of use, only three certified isotope amount ratio reference materials are currently available for Pb: NIST SRMs 981, 982 and 983. Because SRM 981 has a natural Pb isotopic composition, it is mainly used for correcting instrumental mass discrimination or fractionation. This means that, at present, there are no other certified isotope reference materials with natural Pb isotopic composition that could be used for validating or verifying an analytical procedure involving the measurement of Pb isotope amount ratios. To fill this gap, two new reference materials, both certified for their Pb isotopic composition, have been produced together with a complete uncertainty assessment. These new reference materials offer SI traceability and an independent means of validating or verifying analytical procedures used to produce Pb isotope amount ratio measurements. ERM-EB400 is a bronze material containing a nominal Pb mass fraction of 45 mg/kg. ERM-AE142 is a high purity solution of Pb with a nominal mass fraction of 100 mg/kg. Both materials have been specifically produced to assist analysts in verifying or validating their analytical procedures. Note that while one of these reference materials requires the chemical separation of Pb from its matrix (ERM-EB400), the other does not (ERM-AE142). Details on the certification of these isotope reference materials are provided in this report. KW - Lead isotopic composition KW - Isotope ratio KW - Reference material KW - Mass spectrometry PY - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-392060 SP - 1 EP - 16 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-39206 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Vogl, Jochen A1 - Yim, Y.-H. A1 - Lee, K.-S. A1 - Goenaga-Infante, H. A1 - Malinovskiy, D. A1 - Vocke, R. D. A1 - Murphy, K. A1 - Nonose, N. A1 - Rienitz, O. A1 - Noordmann, J. A1 - Näykki, T. A1 - Sara-Aho, T. A1 - Ari, B. A1 - Cankur, O. T1 - CCQM-P134 Pb isotope amount ratios and delta-values in bronze N2 - Isotope amount ratios (hereafter referred to as simply isotope ratios) are proving useful in an ever increasing array of applications that range from studies unravelling transport processes, to pinpointing the provenance of specific samples as well as trace element quantification by using isotope dilution mass spectrometry (IDMS). These expanding applications encompass fields as diverse as archaeology, food chemistry, forensic science, geochemistry, medicine and metrology. However, to be effective tools, the isotope ratio data must be reliable and traceable to enable the comparability of measurement. The importance of traceability and comparability in isotope ratio analysis has already been recognized by the Inorganic Analysis Working Group (IAWG) within the CCQM. Three pilot studies have focused on the quality of isotope ratio determinations (P48 “U isotope ratios in urine”, P75 “stable isotopes in Methionine”, P105 “87Sr/86Sr in wine”). Moreover, isotope ratio measurements are fundamental to IDMS amount of substance determinations. For example, when Pb quantification using IDMS is undertaken, this requires the measurements of Pb isotope ratios. While the requirements for isotope ratio accuracy and precision in the case of of IDMS are generally quite modest, “absolute” Pb isotope ratio measurements for geochemical age dating and source rock characterization as well as forensic provenance and fingerprinting studies require Pb isotope ratio measurements of the highest quality. To support present and future CMCs on isotope ratio determinations, a Key Comparison was urgently needed. Therefore, it was decided at the IAWG meeting in Paris in April 2011 that a Key Comparison on the determination of Pb isotope ratios in a pure Pb solution and in a bronze sample should be organized and accompanied by a pilot study. Measuring Pb isotope amount ratios in a pure Pb solution, while seemingly straight forward, rigorously tests the ability of analyst to correct for any instrumental effects (such as mass discrimination and blank correction) on the measured ratios. Pb, present in trace amounts in a metal matrix sample (e.g. Pb in bronze), provides a real world test of the whole chemical and instrumental procedure, from chemical separation and sample purification to analysis and subsequent correction of appropriate instrumental effects on the separated samples. A suitable bronze material with a Pb mass fraction between 10 and 100 mg·kg-1 was available at BAM. A high purity solution of Pb with a mass fraction of approximately 100 mg·kg-1 was also available. By comparing the Pb isotope ratio results obtained for the bronze sample with the Pb isotope ratio results from the Pb solution, potential biases arising from the processing of the bronze sample could be effectively identified and separated from the instrumental effects arising from the measurement and data processing protocol. KW - Isotope ratio KW - Delta value KW - Molar mass KW - Measurement uncertainty KW - Traceability PY - 2017 UR - https://www.bipm.org/wg/CCQM/IAWG/Allowed/IAWG_Pilot_Studies/CCQM-P134.pdf SP - 1 EP - 42 PB - BIPM (Bureau International des Poids et Mesures) CY - Paris AN - OPUS4-47709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -