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Projeto de investigação
From singing to writing - survey on material prodution and routes of Galician-Portuguese Lyric
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The making of black inks in an Arabic treatise by al-Qalalūsī dated from the 13th c.
Publication . Díaz Hidalgo, Rafael Javier; Córdoba, Ricardo; Grigoryan, Hermine; Vieira, Márcia; Melo, Maria J.; Nabais, Paula; Otero, Vanessa; Teixeira, Natércia; Fani, Sara; Al-Abbady, Hossam; DCR - Departamento de Conservação e Restauro; LAQV@REQUIMTE; VICARTE - Vidro e Cerâmica para as Artes; SpringerOpen
For the first time, this paper systematises the medieval preparation of black writing inks found in the important thirteenth century Andalusian technical treatise written by Muhammad ibn Idrīs ibn al-Qalalūsī (1210–1308). We present the Arabic version of this extraordinary text (‘The gifts of the wise men on the curiosities of the substances’), and its first English translation, as well as discuss key aspects of the processes that remain missing or are unclear indications. In this work, we studied the iron gall inks based on galls, where no other phenolic source is present. In this pedagogical treatise, the recipes for these black iron-gall inks are organised and classified by the gallnuts extraction method used: boiling (decoction), squeezing and infusion, with water being the only solvent used. The inks selected were reproduced and characterised through a multi-analytical approach. Quantification was performed by HPLC–DAD (high performance liquid chromatography with diode array detectors in the UV–VIS), showing that gallic acid is a minor compound in the gall extracts prepared following al-Qalalūsī instructions. In all the recipes, the higher concentration compounds in the gall extracts are the gallotannins pentagalloylglucose and hexagalloylglucose, ranging from 79 to 50% of the phenolic compounds. This supports the results of Raman and infrared spectroscopies. A comparison with medieval Iberian recipes was also done, which served to reinforce our previous results that show water as the sole solvent extracts with much lower yields than mixed solvents (water plus white wine or vinegar).
Towards a Sustainable Preservation of Medieval Colors through the Identification of the Binding Media, the Medieval Tempera
Publication . Vieira, Márcia; Melo, Maria J.; de Carvalho, Luís Mendonça; DCR - Departamento de Conservação e Restauro; LAQV@REQUIMTE; Instituto de Estudos Medievais (IEM); Instituto de História Contemporânea (IHC); Molecular Diversity Preservation International (MDPI)
Medieval colors used in illuminated manuscripts from the 12th to 15th centuries can be at risk. Knowing the binding media used, the medieval tempera, is fundamental to developing new and greener methodologies to increase sustainability in Cultural Heritage. A closer look at the tempera used in medieval illuminated manuscripts kept in Portuguese collections, namely, the Ajuda Songbook (13th c.), the winter breviary (14th to 15th c.), the books of hours (15th c.), and a Renaissance Charter (1512), shows that most of the paints analyzed used a tempera similar to gum mesquite. Infrared spectra were the basis for the differentiation between the gums used in medieval times originating from Prosopis spp. and Senegalia spp., gum mesquite and gum arabic, respectively. The ethnobotanical uses of gum mesquite further engage the reader. This micro review represents a significant step forward in Heritage Conservation, offering new perspectives for innovative and greener treatments. Our research, focusing on the differentiation of gums used in medieval times and the identification of the binding media, has the potential to revolutionize our understanding and the preservation of illuminated manuscripts in Cultural Heritage.
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Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
Concurso para Financiamento de Projetos de Investigação Científica e Desenvolvimento Tecnológico em Todos os Domínios Científicos - 2017
Número da atribuição
PTDC/LLT-EGL/30984/2017