Astromat

U-Pb isotope ratio data set for numerous phosphate (apatite) grains in tin section samples of L chondrite meteorites. Measurements were made in both May 2022 and June 2022. These data were collected using Secondary Ionisation Mass Spectrometry (SIMS) with CAMECA IMS 1280 instruments: one at the Institute of Geology and Geophysics, Chinese Academy of Sciences (IGGCAS) and one at the Stockholm NordSIMS facility at the Swedish Museum of Natural History. The thin sections were coated with gold prior to analysis. Microtextural information was obtained prior to analysis using a combination of back-scatter-electron, cabhodoluminescnece, and electron-back-scatter-diffraction analysis. Data were obtained to test hypotheses relating to the competition between macro-to-meso-scale thermally-driven variation in Pb-loss rates versus microscale variation driven by grain-specific features, e.g., fracture networks. Measurements were made by Dr Sen Hu at the Institute of Geology and Geophysics, Chinese Academy of Sciences (IGGCAS) and Dr Heejin Jeon, Dr Martin Whitehouse, and Dr Craig Walton. Sample preparation, imaging, and data analysis and discussion was conducted by Mr Craig Walton at the University of Cambridge.