Deterioration of the “Quinta Nova Torres Vedras” wall tile panel – an analytical approach

Wall tile panels were commonly used in recreational open outdoors spaces in 18th Century noble houses I Portugal. The nature of their location and the lack of maintenance of such spaces, which lost their purpose during the 20th century, contributed to their natural deterioration. In order to preserve one such panel and facilitate the conservation treatment, it was removed from its location and transported to the facilities of the Polytechnic Institute of Tomar, Portugal. The interest in studying this particular panel was prompted by the advanced stages of deterioration observed in some tiles, where natural succession of biological colonisation and weathering were registered as some of the main deterioration causes. Furthermore, the advanced deterioration stages indicate that removal was a necessary action, as natural weathering would lead to its destruction. The study involved a thorough analysis of the environmental characteristics of the wall placement, the wall materials themselves, the mortar, the ceramic body and the glaze. The methodologies used involved microscopic and laboratory testing to evaluate the extent of lichen colonisation and its influence in the loss of glaze and posterior deterioration of the ceramic body. Results indicate that natural and environmental characteristics, combined with substrate typology and micro-organisms, contribute to accelerate the deterioration process, though appropriate techniques of preventive conservation can be used in specific panels or broader situations. This study will enable the development of innovative methodological and technical approach to the conservation problem here portrayed.info:eu-repo/semantics/publishedVersio

Ground layers in Portuguese Baroque polychrome wooden sculptures: analytical results versus documentary sources

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Clays from Vila Nova da Rainha (Portugal): Appraisal of their relevant properties in order to be used in construction ceramics

The clay deposit of Vila Nova da Rainha (VNR) is included in the lithostratigraphic forma tion named “Argilas de Tomar”, and is located at the lower section of the Tert iary Tagus’ river basin. Clay from one quarry is being extracted for the production of construction ceramics. In this work the firing transformations undergone by VNR cl ays containing quartz, alkaline feldspar, iron oxy-hydroxides, and clay minerals have been studied. Ca rbonates have not been identified in thes e raw materials. The clay layers can be subdivided in three groups based upon composition and ceramic properties. The first group, VNR0, is represented by smectite-kaolinite sandy-silty clay, the second group (VNR1 and VNR2) corresponds to illite-kaolinite bearing clay and the third group (VNR3 and VNR4) is represented by illite-smectite silty clay. The firing process involves the formation of hematite and mu llite both influencing the technical properties of the fired products. With regards to the ceramic properties assessed at 1100 ºC the first group showed the lowest total shrinkage value (7.35 %) the highest water absorption value (12.2 %) and the lo west mechanical bending strength value (12.0 MPa); the same properties assessed in the second group provi ded the highest firing shrinkage values (7.0-5.0 %), the lowest values of water absorption (0.1-0.2 %) and relatively high mechanical bending strength values (47.8-48.0 MPa); the third group showed firing shrinkage values within the range 3.5-4.2 %, water absorption values within the range 1.4-4.5 %, and the highest mechanical bending strength values (49.2-52.0 MPa). The results of the ceramic properties being appraised indicate that the raw materials being studied are suitable for the production of high-quality construction ceramics, such as brick, roof tile and rustic floor tile.info:eu-repo/semantics/publishedVersio

Gold leaf analysis of three baroque altarpieces from Porto

During the second half of the 17th century and the first half of the 18th century, Portugal experienced a rising altarpiece production and an increased taste for gold application in church decoration. Some examples of this tendency can be found in the northwest of Portugal, particularly in the baroque altarpiece productions of Porto, Braga, Vila Real and Viana do Castelo. Porto was the first area studied and three gilded wood-carved altarpieces from different churches were selected: São Bento da Vitória (SB), Santa Clara (SC) and São Francisco (SF). Qualitative and semi-quantitative analyses of the samples were performed by optical microscopy (OM) of the cross-section using reflected and polarised light, and by scanning electron microscopy (SEM) in combination with energy dispersive spectroscopy (EDS). The main advantages and disadvantages of the use of SEM-EDS were discussed and the results regarding the presence of major and trace elements compared.Pendant la deuxième moitié du xviie siècle et la première moitié du xviiie siècle, au Portugal, est observée une production croissante de retables ainsi qu’une préférence pour l’application d’or dans la décoration des églises. Quelques exemples de cette tendance peuvent être observés dans le Nord-Ouest du Portugal, en particulier dans le cas des retables produits à Porto, Braga, Vila Real et Viana do Castelo. Porto a été la première région étudiée et trois retables en bois doré provenant de différentes églises ont été sélectionnés : São Bento da Vitória (SB), Santa Clara (SC) et São Francisco (SF). Des analyses qualitatives et semi-quantitatives de prélèvements ont été réalisées par microscopie optique (MO) de sections, en lumière réfléchie et polarisée, et par microscopie électronique à balayage (MEB) combinée à un système de spectroscopie en énergie dispersive (EDS). Les avantages et inconvénients de l’utilisation du MEB-EDS sont discutées et les résultats concernant la présence d’éléments majeurs et traces comparés

Exploring the potential of cuttlebone waste to produce building lime

The goal of this study is to find a practicable way to recycle cuttlebone waste in the production of lime. It was studied the behavior of calcium oxide obtained from the calcination of this waste at 900, 1000 and 1100 ºC and, after wet slaking, the produced lime was characterized. All the results were compared to calcium oxide or to hydrated lime obtained from commercial limestone. According to the slaking results, the waste and the limestone calcined at 1000 ºC achieved the R4 (around 13 min to reach 60 ºC) and R5 (60 ºC in 25 s) reactiv­ity class, respectively. Changing the calcination temperature to 900 or 1100 ºC did not promote an increase in the reactivity of the calcined waste. Although less reactive than the calcined limestone, the calcined cuttlebone can be transformed without significant constraint into building lime, since this construction material fulfills the relevant physic-chemical standard specifications.The authors thank VAC Minerais, S.A. (Rio Maior, Portugal) for supplying the commercial limestone, the support of Quadro de Referência Estratégica Nacional (QREN) and R&D units: Techn&Art (UID/05488/2018) and Geobiotec (UID/GEO/04035/2019). They also thank Prof. Dr. Francisco Franco Duro, from the University of Malaga (Spain), for the translations to Spanish language.info:eu-repo/semantics/publishedVersio

“Cristo Ressuscitado”: a redescoberta de uma pintura

Some of the most representative Portuguese monuments with painting collections dating from the XV and XVI centuries are located in the municipality of Tarouca, in Viseu district, south region of Douro valley. One of the most important specimen is the wall painting of Ressureição, in the arcosolium of São Pedro de Tarouca Parochial´s church. This wallpainting stands out by its singularity and rarity, since there is only a few specimens in the region chronologically related. A laboratorial approach was conducted, simultaneously, with the conservation and restoration work. The intervention brought to light unknown aspects of this artwork, namely its Mannerist style, hidden by a total repainting. Some aspects of its chronological and stylistic contexts are discussed, as well the materials employed (pigments – Naples yellow). Accordingly, the analytical conclusions, the methodological details and the iconographic changes are also presented.En el municipio de Tarouca se sitúan dos de los más significativos monumentos portugueses, con un representativo patrimonio de pintura portuguesa de los siglos XV y XVI. Entre los varios ejemplos se encuentra el de la iglesia de San Pedro de Tarouca, con una pintura mural, con el trema de la Resurrección, situada en el arcosolio de la nave de la iglesia. Se trata de una pintura que destaca por su singularidad, existiendo pocos ejemplares de la época en esta región del país. La pintura, por su rareza, fue objeto de estudio y análisis de laboratorio cuando se abordó la intervención de conservación y restauración, que dejó al descubierto una obra de marcado carácter manierista, que se encontraba totalmente repintada. En este sentido se discute el contexto cronológico y estilístico de la obra, se presenta el estudio de los pigmentos utilizados y se describe la metodología de intervención adoptada, dando a conocer los aspectos más relevantes de los análisis, tales como la presencia del pigmento amarillo de Nápoles o las alteraciones observadas en la iconografía de la pintura después de la intervención.No concelho de Tarouca situam-se dos mais significativos monumentos portugueses, comum representativo espólio de pintura portuguesa dos séculos XV e XVI. Entre os vários espécimes encontra-se o da igreja de São Pedro de Tarouca, que integra uma pintura mural, com o tema da “Ressurreição”, situada no arcossólio da nave da Igreja. Trata-se de uma pintura que se destaca pela sua singularidade, existindo poucos exemplares desta época nesta região do país. A pintura, pela sua raridade, foi objecto de estudo e análise laboratorial aquando da intervenção de conservação e restauro, que deixou a descoberto uma obra de carácter marcadamente maneirista, que se encontrava totalmente repintada. Neste sentido, discute-se o contexto cronológico e estilístico da obra, apresenta-se o estudo dos pigmentos utilizados e descreve-se a metodologia de intervenção adoptada, dando a conhecer os aspectos mais relevantes da sua análise, tais como a presença do pigmento amarelo de Nápoles ou as alterações observadas na iconografia da pintura após a intervenção

Characterization of Lime Mortars from an 18th Century River Tagus Quay (Lisbon, Portugal)

The monumental quay Cais das Colunas was built in the decades 1770 to 1790, merged in the reconstruction plan of the city of Lisbon after the great 1755 earthquake. Characterization studies of mortars from this period are still very few. In 1997 the quay was partially dismounted and in 2008 was reconstructed. During the reconstruction intervention ancient mortars, from the core, were sampled in order to study them. This paper presents the mineralogical, chemical and granulometric characterization and capillarity water absorption of samples from these mortars. The analytical methodology comprised: the qualitative mineralogical analysis by powder method of total sample by X-Ray diffraction; the quantitative chemical analysis of total sample by X-Ray fluorescence; the water absorption by capillarity coefficient; the determination of hydrochloric acid insoluble residue; and the granulometric analysis of insoluble residue. This methodology allowed determining the simplified composition of mortars. It was confirmed the use of local sands and aerial lime based binder.info:eu-repo/semantics/publishedVersio

Characterisation of the mural paintings from the Misericordia Church of Odemira (Portugal)

Several mortars from mural paintings were collected from the Misericórdia Church of Odemira and analysed by using different techniques namely X-ray diffraction, thermogravimetric analysis with differential thermal analysis, SEM-EDX, optical microscopy, CHNS elemental analysis and chemical analysis. Microfragments of paint layers were collected and analysed by microchemical analysis. The results showed that the mortars are aerial lime mortars with siliceous aggregates and that the pigments used were from local sources

Restitución formal y funcional de un horno romano de la alfarería de Quinta do Rouxinol (Seixal, Portugal): arqueología experimental, control de condiciones de cocción y análisis del material cerámico

La terrisseria romana de Quinta do Rouxinol (Seixal, Portugal) produïa àmfores i ceràmica comuna entre els segles III i V. Una exposició dedicada al jaciment va incloure un model d’un dels forns terrissaires. La seva construcció es va basar en la recerca arqueològica i etnogràfica així com també en la digitalització 3D amb tecnologia làser i fotogrametria de l’estructura original. Un forn similar ha permès testar i avaluar les presumptes solucions productives en un workshop d’arqueologia experimental. El forn es va emplenar de rèpliques d’àmfores i altres ceràmiques. Les condicions de cocció han estat monitoritzades i les pastes ceràmiques analitzades per DRX i FRX.The Roman kiln centre of Quinta do Rouxinol (Seixal, Portugal) produced amphorae and common ware from the third until the fifth century. In the context of an exhibition dedicated to the archaeological site the model of one of the kilns was built. The model was made based upon the archaeological record and some ethnographic research but also by the digital recording of the remains with 3D laser and photogrammetric technologies. A similar kiln was tested and the supposed production techniques evaluated during an experimental archaeology workshop. The kiln was fulfilled with amphorae and common ware replicas. The conditions were controlled and the clay and ceramic matrix were analysed by XRD and XRF.info:eu-repo/semantics/publishedVersio