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The only surviving Medieval codex of Galician-Portuguese secular poetry
Publication . Vieira, Márcia; Nabais, Paula; Hidalgo, Rafael Javier Díaz; Melo, Maria J.; Pozzi, Federica; DCR - Departamento de Conservação e Restauro; LAQV@REQUIMTE; SpringerOpen
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.
Between past and future
Publication . Melo, Maria João; Nabais, Paula; Vieira, Márcia; Araújo, Rita; Otero, Vanessa; Lopes, João; Martín, Lourdes; LAQV@REQUIMTE; DCR - Departamento de Conservação e Restauro; Instituto de Estudos Medievais (IEM); VICARTE - Vidro e Cerâmica para as Artes; Elsevier
Heritage materials are highly complex systems of unknown and intrinsically heterogeneous compositions and unmonitored long-term modifications. In this microreview, we describe our interdisciplinary approach, its importance to new treatments tailored to prevent changes to historical colours, and innovative strategies for their identification in artworks. We illustrate our methodology through the study of medieval Islamic manuscripts from the Fondo Ka'ti. These advanced studies have shown the remarkable properties of ancient dyes, their resilience and durability, properties designed by our ancestors through sustainable materials processing. This lost knowledge can be shared with the community empowering them to create new sustainable applications, from unique art pieces to regional value-added products.
The Colors in Medieval Illuminations through the Magnificent Scriptorium of Alfonso X, the Learned
Publication . Vieira, Márcia; Melo, Maria João; Nabais, Paula; Lopes, João A.; Lopes, Graça Videira; Fernández, Laura Fernández; DCR - Departamento de Conservação e Restauro; LAQV@REQUIMTE; Instituto de Estudos Medievais (IEM); MDPI - Multidisciplinary Digital Publishing Institute
This pioneering work studied the medieval color palette of four manuscripts produced in the scriptorium of Alfonso X, king of the Crown of Castile (r. 1252-84), including the Songs of Holy Mary (Cantigas de Santa Maria, in Rich Codex and Musicians’ Codex), Lapidary (Lapidario), and Book of Games (Libro de los juegos). Scientific analysis based on fiber-optics reflectance spectroscopy in the visible and Raman spectroscopy showed a color palette based on lapis lazuli, indigo, azurite, vermilion, red lead, orpiment, yellow ochre, two different greens (bottle green and vergaut), lead white, carbon-based black, and most importantly, brazilwood pinks, reds, and purples. So, it is now the first reported use of this lake pigment in European medieval manuscript illumination. The painting technique is also discussed. The diversity of colors and techniques, with the presence of lapis lazuli, brazilwood lake pigments, purple, and gold, demonstrates Alfonso X’s desire to produce sumptuous manuscripts.
Iron-gall inks
Publication . Melo, Maria Joao; Otero, Vanessa; Nabais, Paula; Teixeira, Natercia; Pina, Fernando; Casanova, Conceicao; Fragoso, Sara; Sequeira, Silvia O.; DCR - Departamento de Conservação e Restauro; LAQV@REQUIMTE; Instituto de Estudos Medievais (IEM); VICARTE - Vidro e Cerâmica para as Artes; DQ - Departamento de Química; CENIMAT-i3N - Centro de Investigação de Materiais (Lab. Associado I3N); SpringerOpen
Iron-gall inks are an essential element of our written cultural heritage that is at risk of a total loss due to degradation. This degradation leads to the loss of the support, particularly the cellulose-based support. Intending to stabilize it, we have come a long way from the nineteenth-century cellulose nitrate laminations to the relatively recent phytate treatments; nevertheless, less invasive treatments are needed. To pave the way for developing safer and more sustainable treatments, tailored as much as possible to the object, this paper reviews the conservation treatments and the advances that have taken place over the last decade in our understanding of the degradation mechanisms of iron-gall inks, based on a careful selection of references to support a concise microreview. This discussion is based on the currently accepted models based on the Fe3+-gallate and the identification of degradation products for iron-gall inks observed in heritage objects, including manuscripts dating from the fourteenth to seventeenth centuries and drawings from the fifteenth to nineteenth centuries. The degradation promoted by iron-gall inks induces scission of cellulose through acid catalysis and/or redox reactions. The causes of these acid-base and redox reactions are also assessed. Finally, we detail the state-of-the-art conservation treatments used to mitigate iron gall ink deterioration, covering treatments from the late nineteenth century to the beginning of the twentieth century, followed by the presentation of current phytate treatments and new postphytate treatments.
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Fundação para a Ciência e a Tecnologia
Programa de financiamento
3599-PPCDT
Número da atribuição
PTDC/LLT-EGL/30984/2017