Mössbauer study of iron gall inks on historical documents Lerf, A. Wagner, F. E. Dreher, M. Espejo Arias, María Teresa Pérez Rodríguez, J. L. Mössbauer spectroscopy Iron gall inks IGI Historical documents Fe(II)-oxalate Jarosite AL designed and coordinated the practical and scientific work, was involved in the evaluation and interpretation of the data and wrote various drafts of the paper. FEW designed and coordinated the practical and scientific work, performed the Mössbauer spectroscopy, evaluated and interpreted the data and wrote the final version of the manuscript. MD carried out the pH measurements of the papers and determined the nature of the papers and gave valuable hints to research on historical documents. TE provided the fragments of the two Spanish documents. JLPP proposed this investigation and gave valuable hints on the documents. All authors read and approved the final manuscript. Iron gall ink was used in the Western world as a permanent writing material already in late Roman times and throughout the Middle Ages, until it became obsolete in the twentieth century. There is much interest in experimental methods to determine the state of the ink and its degradation products on historical documents. Mossbauer spectroscopy with Fe-57 is such a method, and it has the particular advantage to be sensitive to the chemical bonding of iron, but this method has only rarely been applied to historical documents. In this paper we present Mossbauer data for two damaged documents from a Library in Granada and a handwritten German book from the eighteenth century. In addition to the inked parts of the manuscripts, ink-free parts were studied to determine the amount and chemical state of the iron in the papers. These new results are discussed in the context of previously published Mossbauer data. In one of the investigated documents Fe(II)-oxalate, FeC2O4 center dot 2H(2)O, was observed. The assignment of the various Fe3+ sites in the different documents is rather difficult and often there is a superposition of various species. Known forms of iron gallate are definitely not present on the inked papers. The observed ferric species can be remains of Fe3+ polyphenol complexes of the ink, complexes of Fe3+ with degradation products of the cellulose of the paper or gum arabic, or very small iron oxide or hydroxide nanoparticles. 2021-06-01T07:45:38Z 2021-06-01T07:45:38Z 2021-05-03 info:eu-repo/semantics/article Lerf, A., Wagner, F.E., Dreher, M. et al. Mössbauer study of iron gall inks on historical documents. Herit Sci 9, 49 (2021). [https://doi.org/10.1186/s40494-021-00522-3] http://hdl.handle.net/10481/68954 10.1186/s40494-021-00522-3 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Springer