Calibration and Method Validation for Lead (Pb) Isotope Ratio Measurements performing by ThermoFisher Neptune Plus Mass Spectrometer in the NEPTUNE-TIMS Laboratory (Istituto di Geoscienze e Georisorse, CNR di Pisa)

We describe here in detail the results and the setup of the high precision Pb isotope ratio analysis performed by Multi Collector Inductively Coupled Plasma Mass Spectrometer (MC ICP MS), Thermo Scientific Neptune Plus TM. We performed this method adding thallium (Tl) as an internal isotopic standard to correct mass dependent isotopic fractionation. We also report the procedures for the chemical separat ion and purification of Pb from geological matri ces such as silicates , sulfides and historical artefacts . We report the data obtained on the international certified standard material SRM NIST 981 measured with MC ICP MS Neptune Plus, focusing on the accuracy and reproducibility of the analyses performed in the Neptune TIMS Laboratory (IGG-CNR in Pisa, Italy), and highlighting the advantages brought by the installation of this new mass spectrometer.