A first insight on the biodegradation of limestone - the case of the World Heritage Convent of Christ

The present study is a multidisciplinary approach applied to architectural stone materials of the Convent of Christ in Tomar (Portugal) in order to understand and mitigate the active decay processes. The structure and appearance of the stonework from the Convent of Christ are strongly affected by stains, biofilms and structural degradation. To investigate these phenomena, a multianalytical approach comprising X-ray microdiffraction, scanning electron microscopy, microRaman and microinfrared spectroscopy was applied to the examination of altered outdoor stone areas being detected calcium oxalates, carotenoids and microbial proliferation. The presence of these alteration products seems to be correlated with the microbial activity of bacteria, microalgae, cyanobacteria and filamentous fungi. This work showed that the application of complementary methodologies is an efficient strategy to characterise the stone decay, and constitute a starting point for successful conservation intervention plans that are urgent to ensure the preservation and safeguard of this emblematic monument.

Characterization of traditional raw materials used in housing construction in Huambo Region - Angola

The sustainability of buildings associated to the use of raw earth has motivated the studies and the development of techniques and methods in the context of this type of construction. In the region of Huambo, Angola, these construction techniques are widely used, especially for low-income families who represent the majority of the population. Much of the buildings in Huambo province are built with adobe. Due to the climate in this region, subtropical, hot and humid, with altitudes above 1000 meters and extensive river system, these buildings are particularly vulnerable to the action of water and develop, in many situations, early degradation. The Huambo Province is located in central Angola, has 36 km2 area and approximately 2 million inhabitants. This work aims to evaluate, by conducting in-situ tests, physical and mechanical properties of adobe blocks typically used in the construction of those buildings. The methodology is based on field campaigns where in-situ expeditious tests were performed in soils (smell test, color, touch, brightness, sedimentation, ball, hardness, etc.) and tests on adobes blocks made with traditional procedures, particularly in terms of durability and erodibility (erosion test at Geelong method; evaluation test of wet / dry cycle, applying the New Zealand standards 4297: 1998; 4297: 1998 and 4297: 1999). The results will contribute to the characterization of the geomaterials and methods used in construction with earth in Huambo Province, contributing to the improvement of these sustainable solutions, with a strong presence in this region. The results of this study will also contribute to the proposal of constructive solutions with improved performance characteristics, comfort, safety and durability.

Glimpses of British Guiana at the Colonial and Indian Exhibition, 1886

This paper uses the example of the British Guiana Court at the Colonial and Indian Exhibition of 1886 as a case study to demonstrate how British Guiana (now Guyana) was represented in Britain at the time, by cross-referencing different materials (e.g. objects, correspondence, reports, and newspapers from that period). This exhibition also shows which raw materials from the British Guiana were of interest to Britain and the involvement of Royal Botanic Gardens, Kew in this matter. Nevertheless, the exhibition not only displayed objects and commodities, such as the case of sugar, but also displayed people. Here, particular attention is paid to the Amerindians who were portrayed as living ethnological exhibits at the exhibition. This paper aims to understand how British Guiana was seen and administered by its mother country and also how Everard im Thurn (1852-1932), the explorer, sought to manoeuvre that representation, as well as his relation with RBG, Kew. Taking into consideration that this colony was a neglected area of the British Empire, even in im Thurn’s time, this exhibition was an opportunity not only to display the empire but also for advertising the potential of the neglected colony and to ensure that it would not be forgotten.

A new look into the archaeological materials from the Museum of Évora, Portugal – the case study of the Zambujeiro Dolmen

This paper presents the results of a multidisciplinary and multi-analytical study of the amber beads, red pigments, lithic arrowheads and selected ceramics from the Museum of Évora’s collection of the Zambujeiro Dolmen. Amber beads were studied by Attenuated Total Reflectance Fourier Transformed Infrared Spectroscopy (ATR-FTIR) and Pyrolysis coupled to Gas Chromatography and Mass Spectrometry (Py-GC/MS) to confirm their chemical nature and provenance. The red pigments, frequently found in funerary Neolithic context of the Iberian Peninsula, were studied with micro-Raman, and Scanning Electron Microscopy coupled to Energy Dispersive X-Ray Spectroscopy (SEM-EDS) to identify their chemical nature and provenance. The lithic arrowheads were analysed by portable X-Ray Fluorescence (p-XRF), micro X-Ray Diffraction (XRD), SEM-EDS, and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The ceramic materials were studied to infer provenance and production technology by p-XRF, XRD and SEM-EDS; ceramic contents were evaluated by GC/MS. The studies have shown that while some materials travel hundreds or thousands of kilometres to arrive to the Zambujeiro Dolmen, local materials were also used in the items selected by the communities to honour their deceased.

The fingerprinting of the materials used in portuguese illuminated manuscripts: origin, production and specificities of the 16th century Anttiphonary paints from the Biblioteca Pública de Évora

This thesis focuses on the characterization of materials utilized within the illuminations of Codex 116c of Manizola, a large 16th century antiphonal housed in the Biblioteca Pública de Évora (BPE). Using various spectroscopic techniques (XRF, FTIR, Raman and SEM-EDS), a selection of illuminations were analyzed for pigment and binder identification. The manuscript was further analyzed using fiber optic reflectance spectroscopy (FORS), a non-invasive and portable analysis method ideal for use in illuminations. Using historical documentation and results gained from more extensive analysis of the manuscript, a collection of reference paint samples were created to be analyzed using this method. These samples serve as a reference not only to assist in the identification of pigments used within the manuscript, but also for future studies on similar materials allowing for a better understanding of manuscript production during the 16th century; RESUMO: O presente trabalho é dedicado à caracterização dos materiais utilizados na produção das iluminuras do Codex 116c da Manziola do espólio da Biblioteca Pública de Évora (BPE). Trata-se de um antifonário de grandes dimensões produzido no séc XVI que deverá ter pertencido à Livraria de São Bento de Cástris. A identificação dos materiais utilizados na produção das iluminuras pode ser feita através de análises científicas. No entanto, alguns dos componentes das tintas utilizadas, especialmente os pigmentos orgânicos (lacas) e algumas misturas, apresentam obstáculos à sua identificação por métodos não invasivos. Através de várias técnicas espectroscópicas (XRF, FTIR, Raman e SEM-EDS), foi analisado um conjunto representativo de iluminuras, de modo a identificar os pigmentos e os ligantes presentes nas tintas. O manuscrito foi também analisado por FORS, um método portátil e não invasivo, ideal para a análise de iluminuras. Com base em documentos históricos e nos resultados analíticos, foi criado um conjunto de amostras de referência para ser analisado com FORS. Com esta abordagem, pretende-se que estas amostras, especialmente as de lacas, sirvam de referência não só na identificação dos pigmentos no manuscrito como em estudos sobre materiais semelhantes, contribuindo para um conhecimento mais aprofundado sobre a produção de manuscritos no séc XVI.