The lithium isotope composition of international rock standards

We present the results of analysis of the Li isotope composition of open ocean seawater, nine international rock standards and a C1 chondrite. In addition, we suggest some modifications of the chemical preparation techniques for analysis of lithium isotopes in low concentration samples that give precise isotope ratios by thermal ionisation mass spectrometry (TIMS). The aim of this study is to provide a benchmark for ensuring the reliability of Li isotope data between different laboratories by TIMS and other isotope ratio techniques, including multi collector-inductively coupled plasma-mass spectrometry and ion probe.