4dd9d148-4d05-ee39-e063-3050940a11a6 English nonGeographicDataset non geographic dataset British Geological Survey +44 115 936 3100 Environmental Science Centre,Keyworth NOTTINGHAM NOTTINGHAMSHIRE NG12 5GG United Kingdom enquiries@bgs.ac.uk pointOfContact 2026-06-25 UK GEMINI 2.3 http://data.bgs.ac.uk/id/dataHolding/13608658 Fe-X-ray Absorption Near Edge Spectroscopy (Fe-XANES) spectra from clinopyroxene powders and crystals with known and unknown Fe3+/FeTotal contents with supporting major element compositions from EPMA and crystal orientation data from EBSD 2026-03-23 creation http://data.bgs.ac.uk/id/dataHolding/13608658 Fe-X-ray Absorption Near Edge Spectroscopy (Fe-XANES) spectra from clinopyroxene powders and crystals with known and unknown Fe3+/FeTotal contents with supporting major element compositions from electron probe microanalysis (EPMA) and crystal orientation data from electron backscattered diffraction (EBSD). These data were collected in support of an article titled: 'Estimating Fe valence in magmatic clinopyroxene crystals: Fe-XANES versus electron microprobe'. Clinopyroxene crystals with known Fe3+/FeTotal contents were sourced from collections at the University of Manchester and Manchester Museum, and have been described previously by Neave et al. (2024a; doi: 10.1007/s00410-023-02080-2). Clinopyroxene crystals with known Fe3+/FeTotal contents are from Skuggafjöll (Iceland) and Pico Island (Azores) and have been described previously by Neave et al. (2024b; doi: 10.1007/s00410-024-02144-x). These data were acquired as part of David A. Neave's NERC IRF (NE/T011106/1) between January 2020 and February 2023. Fe-XANES was performed at Diamond Light Source Beamline I18 (SP31428) in February 2023. EPMA was performed at the University of Bristol in Spring 2022. Electron Backscattered Diffraction (EBSD) was performed the University of Liverpool in May 2023. These data were collected to evaluate whether Fe-XANES, which has seen increasingly widespread use for determining Fe valence in isotropic glasses and minerals in recent years, could be routinely used to determine Fe valence in large numbers of anisotropic clinopyroxene crystals. Our motivation stems from ultimately seeking to develop new tools for estimating oxygen fugacity from magmatic clinopyroxene crystals. This work was initially designed to capitalise on two articles on clinopyroxene Fe-XANES that have since been retracted without further comment; we thus present an evaluation that transparently highlights the myriad challenges associated with clinopyroxene Fe-XANES. This repository contains EPMA, Fe-XANES and EBSD data supporting the manuscript; Neave, D. A., Mariani, E., Stewart, A. G., Hartley, M. E., Shorttle, O., & Humphreys, M. C. S. (2026). Estimating Fe valence in magmatic clinopyroxene crystals: Fe-XANES versus electron microprobe. Advances in Geochemistry and Cosmochemistry, 2(1), 1061. https://doi.org/10.33063/agc.v2i1.1061 Dr Madeleine Humphreys University of Durham Department of Earth Sciences Durham DH1 3LE not available originator Dr Margaret Hartley University of Manchester School of Earth and Environmental Sciences Manchester M13 9PL not available originator David Neave University of Manchester Department of Earth and Environmental Sciences Oxford Road Manchester M13 9PL not available originator Oliver Shorttle University of Cambridge Department of Earth Sciences Downing Street Cambridge CB2 3EQ not available originator Elisabetta Mariani University of Liverpool United Kingdom not available originator Alexander G. Stewart University of Manchester United Kingdom not available originator Enquiries British Geological Survey United Kingdom not available distributor Enquiries British Geological Survey United Kingdom not available pointOfContact notApplicable https://resources.bgs.ac.uk/images/geonetworkThumbs/4dd9d148-4d05-ee39-e063-3050940a11a6.png Geology GEMET - INSPIRE themes, version 1.0 2008-06-01 publication Spectroscopy Clinopyroxene X ray fluorescence spectroscopy BGS Thesaurus of Geosciences 2022 revision data.gov.uk (non-INSPIRE) Citable Data NGDC Deposited Data dataCentre NERC_DDC otherRestrictions licenceOGL Available under the Open Government Licence subject to the following acknowledgement accompanying the reproduced NERC materials "Contains NERC materials ©NERC [year]" otherRestrictions The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused. Available under the Open Government Licence subject to the following acknowledgement accompanying the reproduced NERC materials "Contains NERC materials ©NERC [year]" English geoscientificInformation 2020-01-01 2025-11-01 PDF file (.pdf) Comma-Separated Values (CSV) file (.csv) Enquiries British Geological Survey United Kingdom not available distributor https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item191847 WWW:DOWNLOAD-1.0-http--download Data download https://doi.org/10.5285/c1900414-3e31-4d85-a2b8-3beacdf54392 WWW:LINK-1.0-http--related Citation Information - Digital Object Identifier (DOI) Neave, D. A., Mariani, E., Stewart, A. G., Hartley, M. E., Shorttle, O., Humphreys, M. C. S. (2026). Fe-X-ray Absorption Near Edge Spectroscopy (Fe-XANES) spectra from clinopyroxene powders and crystals with known and unknown Fe3+/FeTotal contents with supporting major element compositions from EPMA and crystal orientation data from EBSD. NERC EDS National Geoscience Data Centre. (Dataset). https://doi.org/10.5285/c1900414-3e31-4d85-a2b8-3beacdf54392 information nonGeographicDataset non geographic dataset INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology 2011 publication See the referenced specification false Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 publication See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF false Point analyses were performed on polished samples set within epoxy resin blocks and on polished thin sections. Fe-XANES was performed by determining X-ray intensity over an energy range of 7020–7400 eV, using an energy step of 0.5 eV and a counting time of 2 s per step over the 7105–7120 eV energy range that is critical for defining pre-edge structures. The incident X-ray beam was monochromatised using a Si(311) crystal to increase the energy resolution. Aluminium plates were used to attenuate the beam to avoid saturating the detector, with a 0.1 mm-thick plate used for relatively Fe-poor samples like Augite 1 and Diopside, and a 0.25 mm-thick plate used for relatively Fe-rich samples like Aegirine 2 and Hedenbergite. Fluoresced X-rays were analysed with a Vortex ME-4 silicon drift detector positioned at 90° to the incident beam. EPMA was carried out using a JEOL JXA8530F instrument in the School of Earth Sciences at the University of Bristol operated with Probe for EPMA (https://www.probesoftware.com/). Analyses were performed following the procedure described by Neave et al. (2024a doi: 10.1007/s00410-023-02080-2). EBSD was carried out using a Zeiss GeminiSEM 450 instrument equipped with an Oxford Instruments Symmetry 2 EBSD detector in the Scanning Electron Microscopy Shared Research Facility (SEM SRF) at the University of Liverpool. Prior to performing EBSD, all samples were polished with colloidal silica, then coated with a thin layer of carbon. Samples were analysed at an angle of 70° to horizontal, using an accelerating voltage of 20 kV, a beam current of 10 nA, and working distance between 14 mm and 20 mm. These data were acquired by David A. Neave, Elisabetta Mariani, Alexander G. Stewart. Margaret E. Hartley and Madeleine C. S. Humphreys as part of David A. Neave's NERC IRF (NE/T011106/1).