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- Historical Cleaning Methods (1600-1900) For Traditional Easel Paintings - Documentary Analysis Of Written Sources, Reconstruction Of Wood Ash Lyes And Assessment Of Their Impact On Oil PaintPublication . Devesa, Joana Moura; Stols-Witlox, Maartje; Villarigues, MárciaThe condition of restored traditional paintings has been attributed, at least in part, to previous cleaning campaigns, yet without a clear understanding of the correlation between specific methods employed in the past and the damages observed. Knowledge of historical cleaning techniques and materials can offer valuable insights, as direct visual, chemical, and physical evidence on paintings is difficult to identify without such context. To address this gap in knowledge, this doctoral thesis combines a critical analysis of historical written information on cleaning methods for easel paintings with reconstructions of a relevant ingredient, based on wood ashes, and testing on oil-painted surfaces. In doing so, this the-sis offers a comprehensive analysis of what may have been used and when, while providing new insights into ash-based cleaning solutions through a first assessment of their potential impact on oil paintings. Part I presents the results of a systematic and critical investigation of historical information on the cleaning of traditional easel paintings. Data from over 200 written texts-dating from the mid-16th to the late 19th century-was extracted into a purpose-built database. These texts of a diverse nature, which originated from countries such as England, France, and Portugal, include restoration treatises, artists’ manuals, encyclopaedias, and books of secrets. The database enabled the thorough labelling of the details and the refinement, chronological and geographical organisation and extraction of the collected data. Arranging the information chronologically allowed for the identification of trends in the adoption of specific cleaning methods and highlighted the significant role of alkalis, particularly wood ash-based cleaning ingredients. In addition to providing an overview of historical cleaning methods, this section also includes descriptions of ingredients and tools, as well as a review of cleaning-related damages described in the sources. Part II investigates the use and potential effects of wood ashes with an experimental approach. Two main methods for employing ashes were explored. The first required mixing ashes with water, followed by filtering or decanting the liquid (lye) to be used for cleaning. The second method involved directly applying the ashes and water as a mixture-paste to the paint surface. The reconstructions assessed important variables such as the ash type, the proportion of ash to water and storage of both the ashes and the solution, evaluating how this influences the characteristics of the cleaning ingredient. The pH of all the lyes was measured, and their total alkalinity was determined through titration. Dry residues from one of the lyes were also analysed using infrared spectroscopy in attenuated total reflection mode (ATR-FTIR). Both the ashes and the lyes were further characterised using inductively coupled plasma–atomic emission spectroscopy. The results confirmed the potassium-rich composition and high alkalinity of all the lyes. The reconstructed ash-based solutions were applied to naturally aged model oil paints and historical oil paintings with and without varnish, and their impact was evaluated using a multi-analytical approach. Their visual effects were examined through high-resolution imaging, while chemical changes were analysed ATR-FTIR and complemented with focal-plane-array Fourier transform infrared spectroscopy, and scanning electron microscopy with energy-dispersive X-ray analysis. These investigations revealed the ability of ash-based ingredients to cause visible and chemical alterations in oil paints. Some of the observed alterations are consistent with descriptions of damage associated with past cleaning practices, as described in historical sources and described by present-day conservators. The ATR-FTIR results indicate that potassium soaps were formed as a result of wood ash lye exposure, and that these remained within the medium structure even after rinsing. This highlights the potential for lasting chemical changes within the paint film following exposure to these historical agents. Overall, this thesis offers a critical contribution to the knowledge of historical cleaning practices for traditional oil paintings and supports a better understanding of their current condition. Furthermore, the overview of cleaning materials informs on the potential presence of non-volatile residues, which is particularly relevant when interpreting analytical results and planning conservation-restoration treatments. By combining the analysis of written sources with experimental reconstructions, this research delivers an evidence-based assessment of ash-based alkaline ingredients and their possible effects on oil paint.
- PURscCO2: Supercritical carbon dioxide-assisted consolidation of polyester-based polyurethane foams with an alkoxysilane mixturePublication . Soares, Inês; Ferreira, Joana Lia; Casimiro, Teresa; Isabel, Pombo CardosoPolyurethane (PUR) foams are among the most unstable plastics in museum collections. Ideally, consolidation treatments should allow deep and uniform penetration of the consolidant while maintaining or improving the foam’s flexibility. This is especially important for polyester-based polyurethane (PUR-ES) foams, which degrade primarily by hydrolysis, causing drastic losses of cohesion throughout the entire foam network. Current alkoxysilane-based consolidation treatments, such as the combination of 3-aminopropyl(diethoxy)methylsilane (APDEMS) and n-octyltrimethoxysilane (OTMS), have shown promising results in reinforcing PUR-ES foams while enhancing their hydrophobicity. However, traditionally used application techniques present significant limitations, particularly immersion, which is not adequate for large-scale objects as it requires large quantities of solvent. Supercritical carbon dioxide (scCO2) emerges as a potential alternative for the consolidation of PUR-ES foams due to its unique properties combining the relatively high density of a liquid with the low viscosity and high diffusivity of a gas. The premise of this technology is that it may carry the consolidant deeper, acting as both a solvent and carrier, promoting uniform diffusion and deposition, without the use of hazardous solvents or direct handling of fragile objects during treatment. Therefore, with the main goal of finding a more sustainable and effective consolidation treatment for PUR-ES foams, the current study investigates the suitability of scCO2 as a solvent and carrier to diffuse a binary mixture of alkoxysilanes within PUR-ES foams. A key aspect of this research involved assessing the solubility of alkoxysilanes in scCO2 and the foam’s sorption capacity for CO2, as temperature and pressure variations can significantly influence the dissolution and diffusion properties of the consolidant. Understanding these parameters was crucial for designing experimental conditions. Based on a theoretical discussion and validation of the experimental process, a proof-of-concept study was conducted comparing scCO2-assisted consolidation with traditional spray application. Results showed that both methods preserved the visual appearance of treated samples. However, chemical analyses revealed that while spray application primarily led to superficial consolidation, scCO2 treatment promoted a more uniform and in-depth consolidant penetration. Refinements were made to the consolidation process based on the findings from the proof of concept. The impact of PUR-ES foam ageing conditions on the study's representativeness and treatment efficacy, the polymerisation behaviour of alkoxysilane monomers and mixture miscibility in scCO2, were assessed. ATR-FTIR analysis confirmed that the degraded foams used were representative for cross-study comparisons and that there were slight differences between the polymerisation of the monomers in room conditions and in scCO2. Experimental modifications, such as monomer positioning within the reactor, improved mixture homogeneity in scCO2. Other factors influencing polymerisation, such as pH and residual water, were also explored. The study further investigated the impact of varying APDEMS and OTMS ratios, treatment duration, and water addition on consolidant uptake, penetration depth, hydrophobicity, and mechanical reinforcement. Chemical analysis confirmed the presence of the consolidant in all treated samples, although with a heterogeneous distribution (more consolidant on the external surfaces than in the inner layers), likely due to degradation pathways. Water-containing treatments exhibited non-uniform consolidant distribution and lower uptakes, whereas treatments without water yielded higher uptakes (especially with extended exposure to scCO2) and more uniform consolidant distribution within the cell walls. Hydrophobicity assessment revealed inconsistent results, yet higher APDEMS content mainly increased water absorption. Compression-force-deflection tests showed that treated samples behaved like controls and the results were not reproducible, though high data variability limited statistical confirmation. Nonetheless, qualitative observations indicated improved resistance to compression and surface cohesion in consolidated samples. Ultimately, this investigation identifies limitations faced in laboratory-scale testing and provides a framework for further optimising treatment conditions. Future research should focus on expanding the sample dataset, assessing re-treatment and long-term performance, and scaling up to real objects, a crucial step in validating scCO2-assisted consolidation for collections. Overall, this research demonstrates the potential of scCO2 as a viable and sustainable method for consolidating aged PUR-ES foams.
- Tracing Glass in Portugal. A Multidisciplinary Study of Late Medieval and Early Modern Glass (14th-16th centuries)Publication . Cristoforetti, Anna; Coutinho, Inês; Medici, Teresa; Villamariz, CatarinaWhile archival sources reference glassblowers in Lisbon during the 15th century, no corresponding archaeological evidence has been found. The work aims to trace the provenance of glass circulating in Late Medieval Portugal by analysing 13 glass assemblages spanning the 14th to the 16th centuries through chrono-typological that involves the art history and the reproduction of shapes, and archaeometric methods using μ-PIXE (particle-induced X-ray emission) and LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry). This approach seeks not only to identify external imports and trace commercial exchanges but also to address the absence of archaeological evidence for local glass production by investigating the glass itself and exploring whether it is possible to detect signs of domestic manufacture. The results reveal a stylistic and compositional connection to the Mediterranean world of the time, with a soda-lime-silica composition produced using plant ash as a fluxing agent. The study also identifies imported glass objects from Venice and decorative elements linking the materials to Catalonian façon de Venice production. In addition, a distinct set of objects stands out, both stylistically and compositionally unique compared to the rest of Europe, suggesting the possibility of local production. By compiling a catalogue of these glass fragments, this research contributes to the reconstruction of the history of glass production in Portugal. In addition, it offers results that aim to enrich the archaeological database for future comparisons, thereby expanding the knowledge of late medieval and early modern glass in the Iberian context.
- Preserving the craft: Decoding Portuguese Glass Arcana and their RecipesPublication . Santos, Ana Catarina Reis; Coutinho, Inês; Carneiro, Ana MariaThe term arcanum derives from Latin and means "secret". It is the most accurate term to describe personal batch books where glassmakers documented their compositions and experiments, without particular concern for presentation or legibility. These documents accompanied their authors throughout their professional careers, containing empirical know- ledge, trade secrets, and competitive advantages. Glass production in Portugal from the eighteenth to the twentieth century remains a field with many unexplored questions. Studying primary sources from this period—the arcana—offers significant advantages. These records not only confirm what was produced in Portugal during this time but also provide insight into the raw materials used, their origins, and the commercial exchanges involved in the glass industry. The aim of this thesis is to reproduce glass recipes in three colours—amber, blue, and green—found in the four known Portuguese arcana: from Marinha Grande Factory, the glassmakers Castro and Oliveira Guerra, the Gaivotas Factory, and the Northern Portuguese Glass Centre Factory. Beyond the reproduction and validation of the arcana as cultural heritage, the glass samples were chemically, thermally, and mechanically characterised to create a database of compositions produced in Portugal between the eighteenth and twentieth centuries. Until now, knowledge of this chronology has been scarce, as the few existing studies focus on specific case studies, with no comprehensive research covering national glass production as a whole. One of the main conclusions of this thesis is that glass production in Portugal might have been aligned with developments in the rest of Europe. New materials emerging in the industry were incorporated, and objects and compositions were produced with the same technical complexity as those from major European glassmaking centres. The database of reproduced and characterised recipes developed in this study will enable future comparisons with historical objects in national museums, allowing for their accurate provenance and dating. This contributes to the previously proposed hypothesis that Portugal produced high-quality glass.
- Lanterna Magica - Technology and Preservation of Painted Glass Slides for Projection with Magic LanternsPublication . Santos, Ângela Barros; Vilarigues, Márcia; Otero, VanessaMagic lantern is the term, deriving from the Latin lanterna magica, used to designate an early form of a slide projector in which transparent positive images depicted on glass slides (magic lantern slides) were projected onto a white surface such as a wall or screen. The invention of this apparatus in the mid-17th century allowed, for the first time, the projection of illuminated and magnified images to be viewed by collective audiences. The materials and methods applied to produce painted magic lantern glass slides and specific conservation strategies remain an understudied field. As a result, their severe deterioration problems represent an aggravated challenge for conservation professionals. The present work was developed as the first systematic study on the materials and techniques used to produce painted magic lantern glass slides (entirely painted and coloured over printed outlines), bridging the gap between 18th- and 19th-century written and material sources while addressing preventive conservation and restoration challenges. A literature review of 18th- and 19th-century written sources stating the materials and techniques applied in the magic lantern slide production was conducted, allowing for an overview of the types of glass support procured and the colour palette and binders available. The evolution of magic lantern instruments and illumination systems is also explored. Formulations of Winsor & Newton watercolours were investigated, revealing great complexity and individuality depending on the colourant used in each formulation. The context of the use and impact of the magic lanterns in Portugal throughout time was briefly investigated, and two Portuguese collections of magic lantern slides held by the Portuguese Cinematheque – Museum of Cinema (CPMC) and the National Museum of Natural History and Science (MUHNAC) of the University of Lisbon were selected for the present study. These collections’ characteristics are discussed, and the glass support and painting materials used in 48 of their slides, attributed to a European production of the 18th and 19th centuries, were studied by resorting to a multi-analytical approach. The techniques of Energy Dispersive X-Ray Fluorescence spectrometry (EDXRF), Ultraviolet- Visible (UV-VIS) and Raman spectroscopies were applied in situ, and Fourier Transformed Infrared spectroscopy (FTIR) and Surface-enhanced Raman Spectroscopy (SERS) were carried out on micro-samples. EDXRF allied with semi-quantitative analysis by WinAxil program (making use of glass standards from Corning Museum of Glass (Corning, NY, USA) for validation) allowed the identification of four main glass compositional groups: potassium-rich, mixed-alkali, high-lime low-alkali, and synthetic soda-rich glass. These results, along with visual analysis, verified the preference for high-quality glass reported by historical documentation, and the characteristics of each compositional group helped in the slides’ attributions to certain regions and periods of production. By complementing EDXRF with UV-VIS, Raman, and FTIR spectroscopy, it was possible to identify several colourants, including yellow ochre, gamboge, red ochre, cochineal-based lakes, geranium lakes, vermilion, Prussian blue, ultramarine blue, copper-green, and carbon black, and fillers such as gypsum. Regarding these paints’ binding components, FTIR detected terpenoid resins, namely mastic and shellac and the possible presence of oils. Finally, the SERS technique enabled the identification of carminic acid in a reddish micro-sample. These analyses verified the use of a reduced colour palette, the artist’s preference for bright and pure colours, and simple mixtures to create different hues and gradients. This material characterisation unveiled a strong correlation between the glass and painting materials identified in 18th- and 19th-century slides and those described by coeval written sources and enabled the development of a timeline comprising the evolution of glass procured and the colour palette used in the production of painted slides. It was also possible to find differences between manufacturers, countries, and periods, which may help attribute slides more precisely. Finally, the conservation challenges faced by caretakers and conservation professionals were addressed. The state of preservation of more than 350 slides of interest from the Portuguese collections studied was assessed, and the most common damages were identified, some of them resorting to Optical Microscopy. This study demonstrated that the glass and the painting layers are the most fragile and damaged materials that compose these slides. Considering the material knowledge gathered and inputs from national and international institutions shared through a questionnaire, preventive conservation guidelines tailored to painted slide collections were developed to complement current conservation standards. As around 20 % of the slides studied are in poor or very poor conditions and need remedial or restoration actions, and no guidelines for these procedures on painted magic lantern slides were found by the author, this study also explored methods for cleaning painted surfaces and reassembling their glass support. However, a deep investigation regarding consolidation materials and methods for these transparent painting layers is fundamental. This interdisciplinary research offers a valuable contribution to the understanding of painted magic lantern slides, aiming at increasing awareness and appreciation for these collections to ensure their long-term preservation and fruition by present and future generations.
- The safeguard of medieval manuscript illuminations: the conservation science perspectivePublication . Vieira, Márcia Carina Coval; Melo, Maria João; Fernández Fernández, Laura; Pozzi, FedericaThe Ajuda Songbook is a monument to Galician-Portuguese lyrics full of exceptional illumina- tions, but that remained unfinished. Several aspects of its history, including its origin, have been debated for the last decades. The first scientific analysis of the color in this manuscript advanced the knowledge about its execution, placing it at the end of the 13th century, the beginning of the 14th century. On the other hand, its origin has been previously associated with the scriptorium of Alfonso X (the Learned) due to iconographic similarities with the Songs of Holy Mary. This scriptorium was created as part of a cultural enterprise by Alfonso X for translating, compiling, and improving works on several areas of knowledge. This doctoral thesis studies for the first time the materiality of color in the scriptorium of the Learned King, with the analysis of the Rich codex (RBME Ms.T-I-1) and the Musicians' codex (RBME Ms. B-I-2) belonging to the Songs of Holy Mary; the Lapidary (RBME Ms.h-I-15) and the Book of chess, dice and tables (RBME Ms.T-I-6). By implementing a multi-analytical approach reinforced by exten- sive databases, this research has discovered the oldest application of brazilwood paints in Eu- ropean medieval manuscripts within the Alfonsine scriptorium. However, it also contributed to unveiling that the Ajuda Songbook was produced in a similar cultural context as the Alfonsine manuscripts but was not made in the same scriptorium. The medieval colors comprised colorants, binders, additives, and varnishes, resulting in a complex system. For the study of color this research followed the Historically Accurate Re- constructions methodology that consists in the creation of databases of highly characterized references, prepared according to medieval written sources that are then compared with the historical samples. This methodology creates virtuous feedback that permits the validation of the references and a better comprehension of the historical paints' molecular composition and degradation patterns.The brazilwood database was created following thirteen recipes from seven medieval treatises and recipe books. The reconstruction of these recipes permitted their division into three types according to the final color: translucent rose, rose, and red. By applying the lake pigments to the formulation of the architectural pinks of the Songbook, it was possible to obtain a match through infrared spectroscopy, establishing the following quantities for each compo- nent: 19.9% lead white, 4.9% calcium carbonate, 0.4% brazilwood lake, and 74.8% of a poly- saccharide binder with similar signal to mesquite gum. Microspectrofluorimetry coupled with chemometrics highlighted the high similarity between the paints with translucent rose and the Ajuda Songbook. The second database consists of medieval colors applied pure, in a mixture, and in lay- ers, imitating medieval painting techniques and analyzed through a complementary approach using handheld Raman spectrometers and micro-Surface Offset Raman spectroscopy (micro- SORS). The handheld spectrometers showed efficacy in identifying simple or complex paints compared to benchtop equipment. At the same time, the application of micro-SORS demon- strated potential for the analysis of illuminations, as it can uncover the possible stratigraphy of the paint. This research section was fundamental for optimizing the analysis parameters and information acquired with the handheld Raman Mira DS, posteriorly used to analyze the Alfonsine color palette. The analytical characterization of the Alfonsine manuscripts with Fiber Optics Reflec- tance Spectroscopy (FORS) in the visible and handheld Raman spectroscopy (Mira DS), cou- pled with the knowledge obtained from the databases, uncovered a rich molecular color pal- ette based on brazilwood pinks, lapis-lazuli, indigo, azurite, vermilion, red lead, orpiment yel- low ochre, two different greens (bottle green and vergaut), lead white and carbon-based black. It also unveiled the varied painting techniques applied to each manuscript and the similarities and differences with the Ajuda Songbook, such as the application of bottle green and mixture- based purple colors, both inexistent in this last manuscript. This thesis shows the importance of studying in-depth the materiality of colors in medi- eval illuminated manuscripts, how it can increase the knowledge about the history of these objects, and how they should be considered as a whole, produced by a connected and con- stantly changing society.
- From the texts to the laboratory - a study for the preservation of historical grisaillesPublication . Machado, Carla Fabiana Vaz; Palomar Sanz, Teresa; Vilarigues, Márcia"The German term Glasmalerei, or glass painting, most aptly captures what enabled stained glass to move beyond its obvious decorative and practical functions to develop into a powerfully expressive medium." Virginia Raguin, 2003 The work developed throughout this dissertation aimed to rediscover old technologies in the art of stained-glass painting, with the main objective of building a body of knowledge that will add to a better understanding of grisaille paint production, evolution and its alteration mechanisms. In the development of this work, a gathering and critical analysis of historical written sources was done. The grisaille recipes were identified, interpreted, and compared, giving a broad overview of the technical evolution of the production of grisaille paint throughout time. The information gathered from the historical sources also allowed for the development of a systematic study to understand the influence of the raw materials and production methodology on the grisailles layer's long-term stability. A review and comparison of the published analytical data of grisaille compositions from historical samples was also done. This allowed to follow the paint composition evolution throughout time and find production patterns. A slight difference was also observed, mainly regarding 19th-century recipes and samples, when comparing the information collected from the grisaille compositions found in the literature with the information from the historical written sources. Several stained-glass pieces (of fragments) painted with grisaille from different European countries and centuries were selected and studied to add to the information gathered by the literature review. Besides the more common analytical methodologies, a new and rarely used laser-based analytical approach was also tested for chemical and morphological characterisation, proving to gather a more complete and accurate characterisation of the studied material. A simulated corrosion study methodology was developed to better understand the grisaille alteration mechanisms. Reproduced model grisailles, based on the historical recipes were painted and exposed in a high-humidity chamber and in natural conditions in five Portuguese monuments: Temples of Santa Luzia (Viana do Castelo), Monastery of Batalha (Batalha), Monastery of Jerónimos (Lisbon), Church of São Francisco (Évora), and Church of Santo António do Alto (Faro). This study showed that the compatibility between the grisaille and support glasses is one of the main factors for the painted layers' alteration. The interface layer between the support glass and grisaille will be the region more prone to alteration processes. Both degradation products and changes in the grisaille glass-matrix structure were observed and discussed. To conclude, this dissertation was the first study that solely focused on the grisaille paint layers, where a wide range of methods were followed to study this material, allowing for a more extensive understanding of this stained-glass painting material.
- DECODING THE PAST THROUGH PICK-UP DECORATED GLASS: Glass fragments unearthed in Portugal dated to 16th-17th centuriesPublication . Cabral, Maria Francisca Vasconcelos Raposo Pulido Valente Monteiro; Vilarigues, Márcia; Coutinho, Inês; Medici, TeresaThis project provides an overview and a crosscutting investigation about one of the most important and intricate glass decorative techniques of the Renaissance (end of 16th – 17th cen-turies): the pick-up decoration, including millefiori and splash technique. Millefiori (literally means “thousand flowers”) is characterised by the usage of embedded murine (thin sliced glass canes with colourful concentric patterns in cross-section) fused into the surface of its body glass. While, splash technique is characterized by glass objects that have sparkling coloured pints, produced by the fusion of sliced coloured glasses, that are fused in it surface. Different subjects of investigation are linked in this work: I) history and nomenclature, II) production technique, III) a survey of literature on archaeological findings, and IV) compo-sition characterisation of some fragments unearthed from four different Portuguese archaeo-logical sites: Santa Clara-a-Velha Monastery (SCV) in Coimbra, Largo do Chafariz de Dentro (LCD) and Santana Convent in Lisbon (LCS) and São João de Tarouca Monastery (SJT) in Lamego. The present study involves the meticulous selection of 31 glass samples according with its patterns, colour choice and forms representativity. A total of 105 distinct glass layers were chemically analysed, from a comprehensive assemblage of over 200 pick-up fragments. The research conducted by Teresa Medici (2014) played a crucial role in the survey of archaeolog-ical glass fragments/ objects from the late medieval and Modern periods found in Portugal. To ensure the appropriateness of the selected samples for this project, specific criteria were adopted, including: shapes, range of colours, the presence of gold leaf, the occurrence of cor-roded layers, and certain distinctive attributes (e.g., unique decorative patterns like crosses, caravels, flowers, and bird head shapes). In addition to the aforementioned glass fragments, we also performed analyses on four glass waste products, retrieved from LCD (3 fragments) and LCS (1 fragment) sites, to compare their chemical composition with that of the selected pick-up glass fragments. For the material characterization, was adopted a comprehensive approach encompass-ing macroscopic and microscopic observations, as well as compositional characterization was employed to discern the raw materials used in the production of both colourless and coloured glass artifacts. The morphological investigation entailed the application of stereoscopy and optical mi-croscopy. Compositional analysis was carried out utilizing two distinct techniques: 1) particle induced X-ray emission (μ-PIXE) mapping, which facilitated visualization of the distribution of different oxides across various layers, and 2) laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), enabling the determination of the major, minor, trace, and rare earth elements (REE) in the composition. Additionally, μ-Raman spectroscopy was employed to investigate the opacifiers, while UV-Visible reflectance spectroscopy was utilized to assess the presence of chromophores within the glass samples. The analysed coloured glass exhibits a prevailing trend commonly observed in coeval European artifacts: cobalt imparts the characteristic blue hue, while copper contributes to the aventurina, red, and turquoise colours (at different oxidizing states). Iron is responsible for the amber and greenish tinges, whereas manganese accounts for the black colour when accompa-nied by a minimal CoO content. In the case of white-coloured glass, the opacifier employed in all examined layers is cassiterite, as extensively utilized by the Venetian glassmakers. Based on the findings of this study, it can be confirmed that all the examined pick-up glass fragments fall under the category of soda-lime-silica type. However, despite extensive analysis, a definitive attribution to Venetian production was not attainable in any sample. This observation is of particular significance, as pick-up glass artifacts dating from the 15th to 17th centuries are commonly associated with a Venetian origin. Furthermore, one of the geochemical patterns identified in the results for one of the pro-duction remains found in Lisbon (LCS 0003) aligns with approximately 60% of the samples. Combining this finding with the identification of several glass fragments, as pointed out by Teresa Medici (2014), that exhibit distinct morphological characteristics (as gourd-shaped ves-sels and original flower pattern of SCV 360 fragment) are that likely of Portuguese origin. No-tably, most of these fragments were likely produced using barilla ashes as the alkali source, with the principal components associated with the major components of silica sources, here attributed, to a probable Lisbon provenance by taking the graph which combine TiO2/Al2O3 and Al2O3/SiO2 information. By integrating these empirical findings with corroborative historical documentation, it becomes plausible to propose that the revealed 6th geochemical pattern can be probably at-tributed to Portuguese origin. However, it is essential to acknowledge that further compre-hensive investigations are warranted to definitively establish this attribution.
- Produção de documentação para a preservação de património expositivo. Da Fundação Calouste Gulbenkian às Galerias Municipais: O Percurso de Pedro MoraisPublication . Salgueiro, Ana Rita Ferreira dos Santos; Macedo, Rita; Baião, JoanaSituada no campo da Conservação de Arte Contemporânea, esta investigação centra-se na preservação da obra de Pedro Morais, geralmente descrita como anulada ou efémera. Destacado professor na Escola Artística António Arroio, artista intencionalmente marginal aos circuitos comerciais, a obra de Morais mantém-se pouco conhecida, em parte pela escassa representação em colecções, a que acresce a natureza desmaterializada da sua obra. O exaustivo levantamento, inscrição historiográfica e enquadramento crítico do seu trabalho, são aqui entendidos como passo imprescindível para discutir: O que conservar? E como conservar? Defende-se que o resgate da invisibilidade historiográfica potencia directamente o conhecimento, a exposição e o acesso, como formas de preservação. Sobre esse esteio constrói-se um conjunto de questões éticas e práticas que a continuidade da obra de Morais levanta. Que futuro concebia Pedro Morais para a sua obra? Podem todas as obras de Morais conhecer novas activações? Quem assume a responsabilidade na ausência do artista? Quem são os agentes-chave neste processo? Focando o estudo em obras que se enquadram no campo da instalação, esta tese aborda a vida material de obras complexas que necessitam de intervenção externa para serem exibidas, desdobrando-se no tempo, com variações. Ancorada na largamente difundida noção de rede proposta por Bruno Latour, destaca-se a exposição como momento metodológico privilegiado, onde se reúne um conjunto de agentes que importa identificar, seguir e descrever. Fazer obras, noção cunhada por Vivian van Saaze, assume neste contexto um lugar basilar e resume a necessidade de intervenção que o papel do conservador de arte contemporânea actualmente acarreta. Mapeando e articulando os rastos materiais preservado em arquivos, museus e no espólio dos herdeiros, reflecte-se sobre como podem as instituições que preservam a obra de Morais assegurar a persistência da sua obra. Potenciando o legado material de Morais, foram adoptadas ferramentas de trabalho etnográfico, materializando e conservando também a experiência de indivíduos que detêm relevantes memórias orais e conhecimento corporal, tácito e afectivo, fundamental para a activação de obras que podem oscilar entre o estado dormente, em arquivos ou reservas museológicas, e diversas formas de actualização. Assumindo um posicionamento complementar entre teoria e prática, argumenta-se que a regular exposição das obras de Pedro Morais, associada à activa produção de documentação, nomeadamente dossiers de montagem, constitui a mais eficaz ferramenta para desenvolver soluções de preservação adaptadas aos desafios colocados pela produção do artista. Defende-se que tanto a inscrição da sua obra, como a contínua activação expositiva do seu trabalho, são momentos de transmissão, actualização e num quadro deleuziano, de diferença que contribuem para a conservação e futuro do seu legado.
- Ana Vieira, uma casa desconhecida. Documentação e resgate de uma memória.Publication . Gomes, Sofia Alexandra Machado; Macedo, Rita; Silva, RaquelEsta dissertação teve como objetivo estudar um conjunto de instalações da artista portuguesa Ana Vieira (1940-2016) selecionado dentro de um núcleo que conta com 31 instalações realizadas entre 1977 e 2016, das quais 21 estão sob a tutela de seus filhos, Miguel e Paula Nery. Nos últimos anos, tem-se verificado o crescente aumento de espólios de arte contemporânea póstumos. Desprovidos de uma infraestutura necessária, os/as herdeiros/as de artistas têm agora o desafio de preservar e gerir estes legados. Sem a presença do/a autor/a ou a existência de um estudo sério e aprofundado sobre a sua obra ou sem uma documentação que possibilite a preservação e ativação das suas instalações, espólios como o de Ana Vieira correm o risco de desaparecer por carecerem da salvaguarda associada a um enquadramento institucional. Tem-se verificado que as instituições museológicas resistem a adquirir obras sem documentação e/ou que impliquem elevados custos de montagem e de manutenção. Em consequência, muitas obras relevantes no panorama artístico e escolhidas por críticos e historiadores de arte não estão a ser incorporadas em coleções públicas/institucionais. Num país pequeno, como Portugal, e com poucos museus de arte contemporânea, a questão tem uma importância maior. Através de três casos de estudo: Ocultação/Desocultação (1978), O desenho da menina a fugir do seu suporte (2014) e A arte da Fuga (2016), tendo como base a Actor-Network Theory (ANT, Bruno Latour) aplicada por Vivian van Saaze (2013) e a abordagem biográfica desenvolvida por van de Vall et al. (2011), esta dissertação pretende a) analisar a trajetória das obras; b) perceber e discutir as metodologias que melhor se aplicam às caraterísticas e especificidades de cada obra; c) demonstrar como a ativação de uma instalação é um processo colaborativo e dinâmico e de como os vários intervenientes influenciam este processo; d) refletir sobre o processo de tomada de decisão e sobre quem são os/as agentes responsáveis pela preservação e ativação da obra na ausência da artista; e) propor e produzir uma documentação que permita a preservação e apresentação das obras no futuro; e f) pensar como é que esta documentação é produzida e utilizada. Entre 2017 e 2019 acompanhei diversas montagens de instalações em diferentes contextos e instituições, que foram analisadas e documentadas. A ativação das obras foi fundamental para perceber os desafios colocados, as suas complexidades e contextos, assim como as suas caraterísticas. No decorrer da investigação tornou-se claro que o processo de tomada de decisão sem a artista e, agora, dependente de um conjunto de agentes, vai influenciar a trajetória e resultado final da instalação. Confirmou-se que xiv a documentação é fundamental na conservação de obras complexas, mas verificou-se uma tendência para a estabilização da obra, o que por vezes pode não ser a melhor solução para obras que são inerentemente variáveis. Foi evidente a importância de um/a conservador/a/investigador/a nos processos de tomada de decisão e de ativação da obra, papel esse ainda pouco reconhecido e inexistente no contexto museológico e/ou institucional. A instalação, tal como a sua documentação, é um arquivo de potencialidades que necessita continuamente de atualizações e reflexões.