title: Organic dyes in illuminated manuscripts: a unique cultural and historic record.
abstract: In this study, we successfully addressed the challenges posed by the identification of dyes in medieval illuminations. Brazilwood pigment lakes and orcein purple colours were unequivocally identified in illuminated manuscripts dated by art historians to be from the thirteenth to the fifteenth centuries and in the Fernão Vaz Dourado Atlas (sixteenth century). All three works were on a parchment support. This was possible by combining Raman microscopy and surface-enhanced Raman spectroscopy with microspectrofluorimetry. To the best of our knowledge, this is the first time that brazilein, the main chromophore in brazilwood lake pigments, has been unequivocally identified by surface-enhanced Raman spectroscopy in an illuminated work (the Dourado Atlas). Complementing this identification, through microspectrofluorimetry and micro-Fourier transform infrared spectroscopy, it was possible to propose a complete paint formulation by comparison with our database of references; the dark pink hues, in the three case studies, were produced by combining brazilwood pigment lakes and gypsum in a protein- and gum arabic-based tempera. Orcein purple, also known as orchil dye, has been previously identified in medieval manuscripts, dated from the sixth to the ninth centuries. Our findings in fourteenth-sixteenth century manuscripts confirm the hypothesis that this dye was lost during the High Middle Ages, to be later rediscovered.This article is part of the themed issue 'Raman spectroscopy in art and archaeology'.
authors: Department of Conservation and Restoration and LAQV-REQUIMTE, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Monte da Caparica, Portugal mjm@fct.unl.pt.|IEM, Faculty of Social Sciences and Humanities, Universidade Nova de Lisboa, Avenida de Berna 26-C, 1069-061 Lisboa, Portugal.
authors: Maria João
authors: http://orcid.org/0000-0001-7393-6801
authors: MJ
authors: Melo
authors: Department of Conservation and Restoration and LAQV-REQUIMTE, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Monte da Caparica, Portugal.|IEM, Faculty of Social Sciences and Humanities, Universidade Nova de Lisboa, Avenida de Berna 26-C, 1069-061 Lisboa, Portugal.
authors: Paula
authors: P
authors: Nabais
authors: Department of Conservation and Restoration and LAQV-REQUIMTE, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Monte da Caparica, Portugal.
authors: Maria
authors: M
authors: Guimarães
authors: Department of Conservation and Restoration and LAQV-REQUIMTE, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Monte da Caparica, Portugal.|IEM, Faculty of Social Sciences and Humanities, Universidade Nova de Lisboa, Avenida de Berna 26-C, 1069-061 Lisboa, Portugal.
authors: Rita
authors: R
authors: Araújo
authors: Department of Conservation and Restoration and LAQV-REQUIMTE, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Monte da Caparica, Portugal.|IEM, Faculty of Social Sciences and Humanities, Universidade Nova de Lisboa, Avenida de Berna 26-C, 1069-061 Lisboa, Portugal.
authors: Rita
authors: http://orcid.org/0000-0002-9986-6028
authors: R
authors: Castro
authors: Centre for Structural Chemistry, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
authors: Maria Conceição
authors: http://orcid.org/0000-0002-3068-4920
authors: MC
authors: Oliveira
authors: Leigh House, Higher Street, Hatherleigh EX20 3JD, UK.
authors: Isabella
authors: I
authors: Whitworth
keywords: brazilwood; illuminated manuscripts; microspectrofluorimetry; orcein; orchil dye; surface-enhanced Raman spectroscopy