Isotopic Signatures of Carbon in the ‘Los Pobres’ Graphite Mine, Ronda, Spain Neubeck, Anna Gervilla Linares, Fernando Ronda peridotites Graphite formation temperature Raman spectroscopy Carbon isotopes Fluid inclusions We would like to thank Alison Wright at the University of Aberdeen for Raman measurements, Marianne Ahlbom for guidance with ESEM-EDS, and Heike Siegmund for help with bulk 13C measurements Graphite formation temperatures in the ‘Los Pobres’ mine within the Ronda peridotite, Spain, previously reported to be between 770 and 820 °C, have been reinterpreted based on new temperature measurements using Raman spectroscopy. Additional in situ and bulk stable carbon isotopic measurements and fluid inclusion studies contributed to improved understanding of parts of the graphite formation process. Raman spectroscopy revealed that the formation of the ‘Los Pobres’ graphite extends to temperatures as low as 500 °C, indicating a broader temperature range than previously reported. Stable carbon isotopes and temperature estimates suggest two different crystallization events, followed by a late hydrothermal alteration of the host rock. The first event occurred at temperatures higher than ∼600°C, in which crystalline graphite was formed with a mixed 13C composition as a result of the mixing of two different carbon-bearing sources. The second graphite formation event took place below ∼600°C, within the same system, but with lower purity and crystallinity of the graphite. In the third event, the temperature decreased to less than 550 °C, and hydrothermal fluids altered the host rock, precipitating silica and iron oxides in veins penetrating both the host rock and the deposited graphite. 2021-02-12T11:17:42Z 2021-02-12T11:17:42Z 2020-03-18 info:eu-repo/semantics/article Anna Neubeck, Curt Broman, Magnus Ivarsson, Nils G Holm, Martin Whitehouse, Sara Nilsson, Wolf Geppert, Fernando Gervilla, Isotopic Signatures of Carbon in the ‘Los Pobres’ Graphite Mine, Ronda, Spain, Journal of Petrology, Volume 61, Issue 4, April 2020, egaa042, [https://doi.org/10.1093/petrology/egaa042] http://hdl.handle.net/10481/66505 10.1093/petrology/egaa042 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Oxford University Press