This study has determined the trace element and the U‐Pb, Sm‐Nd and Sr‐Sr isotope composition of the Sumé apatite (from NE Brazil) to assess its suitability as a primary/secondary reference material for LA‐ICP‐MS. Reproducibility tests demonstrate that one batch (~ 100 g) of the Sumé apatite (Sumé‐570) is uniform in terms of Nd‐Nd and U‐Pb isotope compositions. Bulk isotope dilution TIMS/ICP‐MS and LA‐MC‐ICP‐MS analyses confirm that the apatite is well suited for use as quality control material for Nd isotopes and U‐Pb geochronology. U‐Pb ID‐TIMS analyses yield weighted mean ratios of 0.09211 ± 0.00053 (2s; 206Pb*/238U) and 0.06120 ± 0.00063 (2s; 207Pb*/206Pb*) and a weighted mean 206Pb*/238U date of 568 ± 3 Ma (95% c.l.). U‐Pb LA‐(SF/MC)‐ICP‐MS runs using Sumé‐570 as a primary RM and reproduces the dates of other established RMs within 1% deviation (except for Durango 2–4%). Major and trace element abundances show that Sumé‐570 is a fluorapatite derived from a syenitic source. It also strongly shows LREE‐enriched chondrite‐normalised REE patterns with significant negative Eu anomalies, due to crystallisation of plagioclase in the residue.

ICP-MS data reduction. It has been developed to provide easy interaction with and visualisation of LA-ICP-MS U-Pb datasets, and allows fast and reliable data reduction of hundreds of data-points. Saturn offers dynamic graphic interfaces to quickly view, evaluate, and plot U-Pb and Pb-Pb isotope data. It operates online (or offline), giving the freedom to change parameters and reprocess data at any stage of data acquisition. The main interface allows the user to: (1) choose the best statistics for drift correction, (2) include/exclude offset factors and (3) apply (or not) Pb c corrections in different modes. Signal intensities are displayed in a separate graphic interface that allows users to interact with the time-resolved signal of individual spot analyses. All graphic windows are interactive; any modification to data treatment (e.g., inclusion or exclusion of analyses of reference material, or modification of the timeresolved signal windows) is instantaneously updated on the data tables. Saturn is particularly attractive for beginners in LA-ICP-MS U-Pb geochronology as it is non-commercial, easy to install, and very interactive. Coding information and a version of the software can be accessed at http://www.air.ufop.br.

The Khan River (Namibia) and Bear Lake (Canada) titanites are investigated as potential reference materials (RM) for LA‐ICP‐MS applications. The Bear Lake titanite is texturally and compositionally homogeneous. The Khan River titanite is texturally heterogeneous and characterised by variable trace element compositions and total rare earth element contents. However, both titanites have consistent U‐Pb and Nd‐isotope ratios. U‐Pb isotope dilution‐thermal ionisation mass spectrometry analyses yielded Pbc‐uncorrected intercept ages of 516.3 ± 1.3 Ma (2s, n = 5, MSWD = 2.4) and 1067.81 ± 0.74 Ma (2s, n = 4, MSWD = 0.35) for Khan River and Bear Lake titanites, respectively. Multiple U‐Pb LA‐SF/MC‐ICP‐MS analyses gave consistent Pbc‐uncorrected intercept ages for both, Khan River (517 ± 1/5 Ma, 2s, n = 262, MSWD = 1.5) and Bear Lake (1070 ± 1/11 Ma, 2s, n = 325, MSWD = 0.88). U‐Pb SHRIMP analyses on the same material returned identical (within uncertainty) ages. Khan River and Bear Lake gave internally consistent solution MC‐ICP‐MS 143Nd/144Nd ratios of 0.511587 ± 0.000027 (2s, n = 2) and 0.512321 ± 0.000004 (2s, n = 2), respectively. The 143Nd/144Nd ratios via solution‐MC‐ICP‐MS and LA‐ICP‐MS all agree within uncertainty and suggest that both titanites can be used as RMs for Nd‐isotope analyses.

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