Earth's earliest colonisation of terrestrial environments by iron reducing bacteria. Supplementary Data

Supplementary analytical data of reduction spheroids from the Wollogorang Formation.\nLineage: Produced on TESCAN.\nQuantitative mineral chemical data were obtained using a Tescan Mira3 field emission gun scanning electron microscope (FEG-SEM) fitted with an Oxford Instruments X-MaxN energy-dispersive spectrometer, at the CSIRO Australian Resources Research Centre (ARRC) advanced resource characterisation facility, Perth, Australia. Operating conditions were an accelerating voltage of 15 kV, a beam current of 2.0 nA and a live count time of 100 s. Elemental calibrations were made against a range of natural mineral standards, an XPP matrix correction procedure was used, and count rate was calibrated using a pure cobalt metal standard. Data were collected and processed using the Oxford Instruments AZtec software package.