Maria João Melo, researcher at LAQV - FCT NOVA in the CHARM research group, led a study to figure out the chemical reactions of the components that made writing on paper possible and last for hundreds of years. The research work was developed in collaboration with researchers from LAQV at University of Porto and from the University of Cordoba, and recently published in the Journal Heritage Science.
The fact that historical archives, libraries, museums, writing workshops and even monasteries, currently conserve medieval manuscripts is not only a question of heroes or ordinary people who went through the trouble to save them, passing them down from one generation to the next, or who hid them so they would not be destroyed. The materials used to write and draw upon paper were crucial so that surviving written texts can be read, translated and interpreted nowadays.
In this research work, five medieval inks were prepared using ingredients and methods appropriate to the fifteenth to seventeenth centuries. This was done by analyzing handwritten recipes for making ink, painstakingly searching in several parts of the world such as the Bishop Chancellery in Braga, Portugal, where a 1464 recipe is kept, the School of Medicine Library in Montpellier, with another dated between 1469 and 1480, as well as the Historical Archive of Cordoba Province, dated 1474. The five inks used six centuries ago were possible to be replicated by following the five unpublished documents that included information about ingredients, quantity, proportion, temperature and methods.
The collaborative research between historians and chemists involved translations of texts and procedures outlined in the medieval recipes, making the inks following step-by-step directions contained in the medieval documents and analysis of the chemical reactions of these ingredient combinations, with the aim of finding keys to conserving written heritage.
By means of exact replication and analysis of inks used in the Middle Ages, researchers can determine which treatments historical documents should undergo in order to recover and improve their current condition and, above all, ensure that they will physically last longer.
Rafael Javier Díaz Hidalgo, Ricardo Córdoba, Paula Nabais, Valéria Silva, Maria J. Melo, Fernando Pina, Natércia Teixeira and Victor Freitas