Causes of decay of the Aveleiras House decorative plasters (in Torre de Moncorvo)

This paper presents historical and characterization studies undertaken to: a) clarify technical interpretation of lime-stucco and plasterwork by historic architectural treatises, and b) better understand the intentions of the early designers and plasterers: the used proportions and sizing of materials, the coverage achieved using different plasters, the nature and composition of the materials, and the causes and forms of decay of stuccos and plasters. Historical studies are important for determining the most effective courses of actions with regard to the preservation of cultural heritage, as respectful as possible to the original nature and materials of the historical buildings. The present paper includes the history of the stuccos and plasters as well as the characteristics of the materials used in plastering and the tools to model in relief. In addition, were carried out an “in situ” inspection and laboratorial analysis, as TGA, XRD, EDS and SEM on decorative and plain plasters from Aveleiras House. As a consequence of this study it was possible to quantify the percentage of binder in the mortars and to identify the causes of decorative plasters decay, suggesting their bio deterioration

Mural Paintings Characterisation Using X-ray Fluorescence and Raman Spectroscopy—A Case Study: Nossa Senhora das Neves Chapel, Vilar de Perdizes, Galicia—North Portugal Euroregion

Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/[Abstract]: Sixteenth-century mural paintings of Nossa Senhora das Neves in Vilar de Perdizes (Galicia—North Portugal Euroregion) were analysed. An iconographic study has allowed us to understand the meaning of the seven scenes that constitute the mural painting. X-ray fluorescence (XRF) and Raman spectroscopies determined the compounds used in this mural painting, both in the original and in later repaintings. The black paint was bone black. Hydroxyapatite characteristic bands and those of the associated phosphates have been identified. White lime was used as white paint. Lepidocrocite and goethite were used to make yellows, and hematite was used to make red shades. Cinnabar has been used for a later red repaint. Carbon-based compounds and rutile were used to create different tonalities by darkening or lightening colours. It is of great significance to obtain accurate and reliable mural painting information through scientific means, since preservation, restoration, and repainting without detailed information can be harmful to mural paintings.This work was financed with national funds through FCT -FUNDAÇÃO PARA A CIÊNCIA E A TECNOLOGIA, I.P. of Portugal, under the projects with the references CEECIND/03568/2017, (UIDB/00073/2020), and (UIDP/00073/2020) projects of the I, D unit Geosciences Centre (CGEO) of Coimbra University (Portugal). Ezequiel Vázquez and Ana J. López were beneficiaries of a scientific stay financed by Erasmus+, HERDADE Consortium (2021-1-ES01-KA130-HED-000007519). Pablo Barreiro Castro and D.M. Freire-Lista were beneficiaries of a scientific stay in University of Trás-os- Montes e Alto Douro (UTAD) and A Coruña University (UC), respectively, financed by the IACOBUS program.Portugal. Fundação para a Ciência e a Tecnologia; CEECIND/03568/2017Portugal. Fundação para a Ciência e a Tecnologia; UIDB/00073/2020Portugal. Fundação para a Ciência e a Tecnologia; UIDP/00073/202