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    120 samples of 57 tephra layers identified at IODP Expedition 350 sites (U1436 and U1437) were used in grain size analysis. Some layers have one grain size measurement, others have multiple measurements throughout the tephra layer.

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    Geochemical analyses of melt inclusions, host minerals, and glasses from the 2014-15 Holuhraun eruption, Iceland. Published in: Hartley ME, Bali E, Neave DA, Maclennan J, Halldorsson SA (2018) Melt inclusion constraints on petrogenesis of the 2014–2015 Holuhraun eruption, Iceland. Contrib Mineral Petrol 173:10. doi:10.1007/s00410-017-1435-0

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    Geochemical data has been collected on samples from new exposures of the 1883 deposits, revealed by the 2018 tsunamigenic flank collapse of Anak Krakatau, which provides improved stratigraphic context. Whole-rock data taken by X-ray Florescence shows no systematic stratigraphic correlation. Chemical data for transects across, and spot points on, plagioclase phenocrysts, including some trace element data, all obtained using Electron Probe Microanalysis (EPMA), with Backscatter electron (BSE) images of crystals, obtained using Scanning Electron Microscope, reveal complex zoning profiles. However, chemical data for transects across pyroxene phenocrysts, obtained using EPMA, show this phenocryst phase is largely unzoned. The dataset also includes chemical data for spots on Fe/Ti oxides, included on the rims of pyroxene, and obtained using EPMA. Matrix glass chemistry, obtained via EPMA, shows that the early eruptive ash is more evolved than the pyroclastic material that follows, and that there is a slight overall trend to a more homogenous, less evolved melt composition. The 1883 eruption of Krakatau was a large, cardera-forming eruption that caused approximately 36,000 fatalities. It is also the only eruption of its size to have accompanying written accounts.

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    NERC Grant NE/M011488/1 Electron microprobe analyses of Mn-oxyhydroxide phases as elemental percentages per point analysis. Mn-oxyhydroxide phases were within limonites from Acoje (Philippines), Caldag (Turkey), Nkamouna (Cameroon), Piaui (Brazil) and Shevchenko (Kazakhstan) laterite deposits. The data were acquired during the NERC SoS Minerals CoG3 project between 2015 and 2018 using a Cameca SX100 electron microprobe at the Natural History Museum, London, UK. Point analyses were performed on samples set within epoxy resin blocks, polished and coated with carbon. All elements were analysed using wavelength dispersive X-ray spectrometers. These data were used to identify the Co and Ni bearing host minerals within each natural resource and to assess the amount and variability of these elements within specific Mn-oxyhydroxide phases. This may be useful within the mining sector, resource assessment, processing or prospecting, geo- or material scientists and processing engineers / metallurgists. The data were acquired in the Core Research Laboratories, Natural History Museum by the NHM CoG3 team. NERC grant: CoG3: The geology, geometallurgy and geomicrobiology of cobalt resources leading to new product streams

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    NERC Grant NE/M011488/1 Electron microprobe analyses of Fe-oxide and Fe-oxyhydroxide phases as elemental percentages per point analysis. The phases were within limonites from Acoje (Philippines), Caldag (Turkey), Nkamouna (Cameroon), Piaui (Brazil) and Shevchenko (Kazakhstan) laterite deposits. The data were acquired during the NERC SoS Minerals CoG3 project between 2015 and 2018 using a Cameca SX100 electron microprobe at the Natural History Museum, London, UK. Point analyses were performed on samples set within epoxy resin blocks, polished and coated with carbon. All elements were analysed using wavelength dispersive X-ray spectrometers. These data were used to identify the Co and Ni bearing host minerals within each natural resource and to assess the amount and variability of these elements within specific Fe-oxide or Fe-oxyhydroxide phases. This may be useful within the mining sector, resource assessment, processing or prospecting, geo- or material scientists and processing engineers / metallurgists. The data were acquired in the Core Research Laboratories, Natural History Museum by the NHM CoG3 team. NERC grant: CoG3: The geology, geometallurgy and geomicrobiology of cobalt resources leading to new product streams

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    Geochemical analysis of volcanic samples from Aluto, Fentale, and Kone volcanoes, Ethiopia. Data are referenced in Iddon et al., 2018: Mixing and Crystal Scavenging in the Main Ethiopian Rift Revealed by Trace Element Systematics in Feldspars and Glasses; https://doi.org/10.1029/2018GC007836.