From 1 - 2 / 2
  • Categories  

    This spreadsheet contains 21 oxygen isotope measurements for hematite and mixed hematite/goethite samples from the supergene profiles of the Spence and Cerro Colorado porphyry copper deposits in the Central Andes. Columns are also included which contain calculated isotopic values for weathering fluids which were present at the time of iron oxide formation. These data are presented and discussed in the G-cubed paper 'A rusty record of weathering and groundwater movement in the hyperarid Central Andes' (Shaw et al., 2021). Weathering fluid isotopic values are calculated using the published fractionation factors of Clayton & Epstein (1961), Yapp (1990) and Bao & Koch (1999). The authors have the most confidence in the fluid values obtained using the fractionation factor of Yapp (1990), for reasons outlined in the publication.

  • Categories  

    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