Identity and connections within medieval heritage: color in the illuminated manuscript through the eyes of the molecular sciences and humanities

The characterization and identification of organic dyes is still a challenge within the field of Conservation Science. By exploring the potentialities of microspectrofluorimetry combined with chemometrics, this doctoral project provides the identification of red organic colorants and a comprehensive knowledge of the making of medieval paints. Microspectrofluorimetry (in the visible) allows the simultaneous acquisition of excitation and emission spectra, offering high sensitivity and selectivity combined with good spatial resolution and the possibility of in-depth profiling, which facilitates an accurate identification of dyes and lake pigments. Although lacking the fingerprint capability of vibrational spectra, it offers valuable knowledge into the paint formulation. Recipes’ specificities can provide insight into chronological and location particularities, such as scriptoria, enabling a better understanding of the making of the artists’ materials. The first part focuses on the development and testing of modeling strategies applied to i) a database of historically accurate reproductions of four natural red colorants namely brazilwood, cochineal, kermes and lac dye, used during the Middle Ages; ii) data from artworks, to address the difficulty of analyzing centuries old paints. The first confirmed the potential for microspectrofluorimetry in the assessment of the chromophore’s environment, i.e., the paint formulation, while the second explored the intricacies of the ‘original’ colors and the effectiveness of this methodology to explore similarities between naturally aged paints. This project proves the ability of microspectrofluorimetry as a powerful technique for the characterization of dyes and lake pigments. The historical reconstructions database allowed to pinpoint the main recipes of cochineal lake pigments from the 19th century Winsor & Newton’s database. The artworks database allowed to better understand recipe specificities and for the first time, we could pinpoint a formulation in which lac dye and brazilwood chromophores are admixed, in manuscripts from the Alcobaça scriptorium. In the second part, the methodology developed was tested in two case studies: the Ajuda Songbook and a group of Islamic manuscripts. The first, the oldest of the surviving Galician-Portuguese songbooks, is an unfinished illuminated manuscript, of which there is no knowledge of the circumstances of its production or the reason why it was never finished. The combination of a multi-analytical approach with the methodology developed in this project enabled the complete molecular characterization of the paint colors. It was shown the skillful construction of the paint layers and the richness of the chromatic palette, which demonstrates the desire and the resources to produce a luxurious manuscript. The methodology allowed to propose a production date for the Ajuda Songbook, in which the presence of brazilwood lake pigment and mosaic gold indicates a 14th century date, while the use of orpiment yellow pushes the date back into the 13th century. The second case study is a group of Islamic manuscripts (12th – 15th c.), from Timbuktu, Mali, which due to their rescue and conservation have allowed the study of their materials and techniques. For the first time, the richness and specificities of the paint formulations used were disclosed. It was possible not only to provide an unequivocal molecular characterization of the red colorant, lac dye but also to ascribe specific recipes to the different paint colors. Interestingly, the comparison with the artworks’ database has shown similarities with lac dye formulations found in Portuguese medieval illuminations. Moreover, the full characterization of the paint materials has also revealed severe degradation of the binding media. This approach will allow for better informed decision-making in the conservation process of these manuscripts. The synergy between the multi-analytical approach for the analysis of medieval manuscripts and the new methodology for the study of organic colorants was essential to the study of both case studies. The confocal spectrofluorimetry set-up used, as well as the expertise in the characterization of artworks, enabled in-depth knowledge into the construction of color paints, well beyond the identification of the single fluorophore

tracing history through luxury pink colors

The authors would like to thank José Alberto Ribeiro, director of Palácio Nacional da Ajuda, and Cristina Pinto Basto, coordinator librarian, for their generous support and rewarding collaboration. We also wish to acknowledge the Laboratory of Biopolymers—Centro de Investigación en Alimentación y Desarrollo, A.C (C.I.A.D., A.C.), Hermosillo, Sonora, México, for providing the samples of mesquite gum used in this work. This research was funded by the Portuguese Science Foundation (Fundação para a Ciência e Tecnologia, Ministério da Educação e da Ciência, FCT/MCTES) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265). Project “Try it and you will see that is true”. Recipes and knowledge from Medieval society to the 21th century”, PID2019-108736GB-I00, Ministerio de Ciencia e Innovación. R. J. Díaz Hidalgo, posdoctoral UCO 2020, La producción documental y libraría al Ándalus siglos XIII XV, Plan Propio de Investigación de la Universidad de Córdoba; Publisher Copyright: © 2023, The Author(s).The Ajuda Songbook is an exceptional illuminated manuscript being the only surviving codex of Galician-Portuguese secular poetry; it was produced in the end of the thirteenth century, beginning of the fourteenth century. The diversity of colors accentuated by the presence of lapis lazuli blue and brazilwood pink, demonstrates the desire to produce a sumptuous manuscript. Pink is, in this context, a luxury color and its identification attests to one of the earliest known occurrences of brazilwood in artworks. Scientific analysis showed, for the light pinks, a different formulation from that found in fifteenth-century books of hours and from all historical reconstructions of these colors prepared to date. This knowledge was used to further expand a database previously built in our laboratory and applied to the characterization of pink shades in the Ajuda Songbook. Thirteen brazilwood recipes were selected from seven Medieval treatises and reference materials were prepared based on such historical information. Three types of colors were achieved, defined as translucent rose, rose, and red. The translucent rose was obtained from recipes where egg white is used for extraction, and no other additives are present; rose from recipes with calcium carbonate; and red from a wider range of recipes, in which these ingredients are not mentioned. These colors were then prepared as paints, and analytical results were thus compared with data from the light pinks seen in the Ajuda Songbook’s architectural backgrounds. We were able to reproduce the pink very well using infrared spectroscopy, identifying its main ingredients: calcium carbonate as filler; lead white as the pigment that produces light pink; and the binder as a polysaccharide with a fingerprint similar to mesquite gum. For the chromophore color, the application of chemometrics approaches to molecular fluorescence spectra highlighted a high degree of similarity with the paint reconstructions.publishersversionpublishe

UV-Vis spectroscopy

UV-Vis reflectance spectroscopy has been widely used as a non-invasive method for the study of cultural heritage materials for several decades. In particular, FORS, introduced in the 1980s, allows to acquire hundreds of reflectance spectra in situ in a short time, contributing to the identification of artist's materials. More recently, microspectrofluorimetry has also been proposed as a powerful non-invasive method for the identification of dyes and lake pigments that provides high sensitivity and selectivity. In this chapter, the concepts behind these spectroscopic methodologies will be discussed, as well as the instrumentation and measurement modes used. Case studies related with different cultural heritage materials (paintings and manuscripts, textiles, carpets and tapestries, glass, metals, and minerals), which show the usefulness of UV-Vis reflectance spectroscopy and microspectrofluorimetry applied to the study of artworks, will also be presented.publishersversionpublishe

Composition Analysis of Writing Materials in Cairo Genizah Documents

This work investigates the different writing materials in use in Egypt during the 11th century and the reason for their diversity.; Readership: Academics and specialists working in the Cairo Genizah and in writing material characterization

Detecting Forgery: Forensic Investigation of Documents

Detecting Forgery reveals the complete arsenal of forensic techniques used to detect forged handwriting and alterations in documents and to identify the authorship of disputed writings. Joe Nickell looks at famous cases such as Clifford Irving\u27s autobiography of Howard Hughes and the Mormon papers of document dealer Mark Hoffman, as well as cases involving works of art. Detecting Forgery is a fascinating introduction to the growing field of forensic document examination and forgery detection. Seldom does a book about forgery come along containing depth of subject matter in addition to presenting clear and understandable information. This book has both, plus a readability that is accessible to those studying questioned documents as well as seasoned experts. -- Journal of Forensic Identification The author\u27s expertise in historical documents is unmistakably evident throughout the book. Once I began reading, I found it hard to put down. -- Journal of Questioned Document Examination Guides the reader through various methods and techniques of identifying fakes and phone manuscripts. -- Manchester (KY) Enterprisehttps://uknowledge.uky.edu/upk_legal_studies/1000/thumbnail.jp

Composition Analysis of Writing Materials in Cairo Genizah Documents

This work investigates the different writing materials in use in Egypt during the 11th century and the reason for their diversity.; Readership: Academics and specialists working in the Cairo Genizah and in writing material characterization

THE NYANGWE DIARY OF DAVID LIVINGSTONE: RESTORING THE TEXT

This project will build on imaging technology pioneered with medieval parchment palimpsests to create a digital image archive and online scholarly edition of the Nyangwe field diary (1871) of the celebrated Victorian explorer David Livingstone. Although in a fragile, nearly illegible state, the paper diary is of immense historical value because it details the circumstances leading up to Livingstone's famous meeting with Henry Stanley in November 1871, and because it records Livingstone's response to a massacre of the local African population by Arab slave traders' an event that would become a rallying point for late-Victorian abolitionists. Our project will seek to develop technology for the preservation of the diary and recovery of its faded text, and create a model for scholar-scientist collaboration. Our work will make Livingstone's diary accessible to scholars and non-specialists worldwide and produce a template for the display of similar records of Victorian travel and exploration

Promoting Access to Historic Book Structures: A Case Study of the Lord Collection

This project is focused on improving access to the John C. Lord Collection by creating an accessible and adaptable digital catalogue to facilitate use. The 23 volumes in the collection span four centuries and include many different binding structures. Several of the volumes are in bindings contemporary with the text. In 2015 the collection was placed on long-term deposit at the Buffalo State Art Conservation Department from the Buffalo History Museum. The collection has served as a study collection for book conservation students and as a result, the department has generated a large collection of electronic documentation of the collection. Data relating to the collection is stored on the department server but is not easily searchable. If unaddressed, deficiencies in the current system can lead to dissociation of collection records from the items. This project gathered all previously collected data, reports, and studies relating to the collection and created an adaptable finding aid and workflow to facilitate use of the collection