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- Cultural Heritage analysis using Synchrotron Radiation: case studies in Ceramics, Glasses, and Lithologic MaterialsPublication . Veiga, JP; Coutinho, ML; Figueiredo, Elin; Silva, TeresaABSTRACT: Synchrotron radiaton is a powerful tool for non‐destructve analysis of materials in cultural heritage research. It has revolutonized our ability to understand the compositon, structure, and history of cultural heritage objects, leading to significant advances in fields such as archaeology, art conservation, and materials science. Dedicated beamlines for cultural heritage research are available at synchrotron facilites around the world, such as the European Synchrotron Radiation Facility (ESRF), SOLEIL synchrotron, and ALBA synchrotron, providing specialized support and instrumentation for high‐resolution analysis of cultural heritage objects using various techniques, such as X‐ray absorption spectroscopy, X‐ray fluorescence, X‐ray diffraction, and X‐ray imaging.
- Co and Cu K-edge XANES study of the glazed tiles from the Fronteira Palace (Lisbon, Portugal) [Poster]Publication . Coutinho, ML; Silva, Teresa; Figueiredo, Elin; Rolim, M.; Salas-Colera, Eduardo; Veiga, JPABSTRACT: The Fronteira Palace located in Lisbon was built during the second half of the seventeenth century. The Palace is known for its unique azulejos (Portuguese glazed tiles) dated from the 17th and 18th century which were profusely used both in the interior of the palace and on its magnificent formal gardens. The gardens have a unique cladding of high relief lustre tiles combined with blue-and-white tiles adorning the Gallery of the Kings (Figure 1). Samples of azulejos from Gallery of the Kings, were characterized in a previous work by PIXE. They display a silica alkali-lead glass or silica alkali glass and chromophores based on Co for the blue colouring and Cu for the red-lustre effect . In fact, the analyses showed that the colourless glaze has a lead-alkali silicate composition and a copper-rich lustre overlay, in agreement with the Manise lustreware production (Spain) after the XVII century. To achieve a comparison between manufacturing techniques and pigments used samples were characterized using X-Ray Absorption Spectroscopy. XANES techniques can provide information on the structural behaviour of transition metals in the vitreous matrix - namely, their bonding state and coordination environment, providing relevant information regarding the Co and Cu as chromophores.
- A XANES approach to the blue pigments in ceramic heritage [Resumo]Publication . Coutinho, ML; Veiga, JP; Ruivo, Andreia; Silva, Teresa; Salas-Colera, Eduardo; Bottura Scardina, Silvia; Lima, Augusta; Figueiredo, Elin; Cotte, Marine; Lima, M.M.R.A.
- Cultural Heritage, Materials Science and Synchrotron Radiation: a perspective from a group of Portuguese usersPublication . Veiga, JP; Coutinho, ML; Silva, Teresa; Figueiredo, Elin; Lima, M.M.R.A.; Saraiva, A.S.; Carvalho, FernandaABSTRACT: In this communication, examples to be presented are related to ancient ceramics, glasses, archaeological slags, inorganic pigments and lithologic materials where we were able to gain new insights into composition, structure and degradation processes, contributing to their preservation and interpretation for future generation.
- An insight into the firing conditions of Chinese blue-and-white porcelain through XANESPublication . Coutinho, ML; Veiga, JP; Ruivo, Andreia; Silva, Teresa; Salas-Colera, Eduardo; Bottura Scardina, Silvia; Lima, Augusta; Figueiredo, Elin; Cotte, Marine; Lima, M.M.R.A.ABSTRACT: Chinese blue-and-white porcelain is found in archaeological excavations worldwide, being significant evidence of global trade routes and cultural exchange. Synchrotron radiation-based techniques have been applied for studying cobalt speciation to establish a correlation between the cobalt and iron oxidation state and local coordination environment in the rich blue shades of Chinese blue-and-white porcelain. However, the relationship between the firing atmosphere conditions and the speciation of cobalt has not been established yet. In this study, underglaze blue models were produced and fired in air or under reducing atmospheres to ascertain the effect of the firing atmosphere in cobalt and iron speciation. The experimental results were compared with data obtained on historical samples of ancient porcelain shards. The microstructure and colour of the produced underglaze blue models were investigated by variable pressure scanning electron microscopy (VP-SEM-EDS), using a hyperspectral imaging camera (Vis-SWIR reflectance spectroscopy) and colorimetry. The formal valence and coordination of cobalt and iron ions of the glaze were determined by X-ray absorption spectroscopy (XAS), particularly X-ray absorption near edge structure (XANES), using synchrotron radiation. Spectral features demonstrated that both cobalt and iron speciation were affected by the firing atmosphere and therefore could be used to ascertain the firing atmosphere.
- A XANES study of the Sn K-edge in slag by-products from tin smelting experiments [Poster]Publication . Figueiredo, Elin; Coutinho, ML; Silva, Teresa; Salas-Colera, Eduardo; Veiga, JPABSTRACT: Tin was a very important alloying element in Western Europe in the production of bronze (Cu-Sn alloy) since the second millennium BC (Bronze Age), when most metallic artefacts were made of this alloy. Smelting experiments using cassiterite collected in the NW Iberian territory were made to produce tin in a very simple and small scale manner, using a small open pit structure to reproduce what could have been the manufacturing process of tin in prehistoric times. Chemical and structural analysis of the products by XRF, SEM-EDS and XRD were made to achieve a detailed knowledge of the characteristics of the materials. Additionally, an X-ray absorption near-edge structure region (XANES) study was performed on three types of slags previously identified (Type 1, Type 2 and Type 3) to obtain information on the oxidation state of Sn. The analyses were made at the European Synchrotron Radiation Facility (ESRF) at the beamline SpLine BM 25A (5-45 keV).