| AVS 64th International Symposium & Exhibition | |
| Applied Surface Science Division | Thursday Sessions |
| Session AS-ThP |
| Session: | Applied Surface Science Poster Session |
| Presenter: | Karen Gaskell, University of Maryland, College Park |
| Authors: | K.J. Gaskell, University of Maryland, College Park A.A. Ponce, University of Maryland, College Park L.B. Brostoff, Library of Congress S.K. Gibbons, University of Maryland, College Park B. Eichhorn, University of Maryland, College Park P. Zavalij, University of Maryland, College Park C. Viragh, The Catholic University of America S. Alnemrat, Naval Postgraduate School at Monterey J. Hooper, Naval Postgraduate School at Monterey |
| Correspondent: | Click to Email |
Iron gall inks were the major writing medium from the middle ages through the 19th Century in the Middle East and Europe, and are present in hundreds of thousands of important cultural heritage objects worldwide, including books, manuscripts and artistic drawings. Iron gall ink depending on its preparation is well known for its potentially corrosive effect on paper or other writing medium, over time, changes in temperature and humidity can accelerate this degradation resulting in the worst case, complete loss of documents. The major ingredients of ion gall ink are iron salts, most often iron sulfate, tannic acids derived from vegetable sources such as gall nuts and gum arabic used as a binder. Despite much research in this area the chemistry of iron gall ink is still poorly understood. Through spectroscopic and structural measurements of synthesized model compounds and authentic documents combined with aging studies, we conclusively show that the main colorant of iron gall ink is an amorphous form of Fe(III) gallate·xH2O (x = ∼ 1.5–3.2). Comparisons between experimental samples and historical documents by XPS, Raman and IR spectroscopy, XRD, and Mössbauer spectroscopy confirm the relationship between the model and authentic samples.