Navegando por Assunto "Azulejos"

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Acesso aberto (Open Access)
Caracterização mineralógica de azulejos de Salvador e Belém dos séculos XVI, XVII e XIX
(2004-12) SANJAD, Thais Alessandra Bastos Caminha; ANGÉLICA, Rômulo Simões; OLIVEIRA, Mário Mendonça de; COSTA, Walmeire Alves de Melo
The present article is a study about the mineralogical composition of ancient tiles from centuries XVI, XVII and XIX, found in Belém and Salvador, in order to interpret the possible raw material and burning temperature. Quartz was identified in all samples. Other crystalline phases found are mullite, cristobalite, calcite, anorthite, hematite, gehlenite, diopside and wollastonite. Based on the probable raw material and probable burning temperature it was possible to organize the samples into three groups: group 1 - kaolinite and quartz, T between 1200º and 1728º C; group 2 - kaolinite, calcite and/or dolomite and iron oxide or hydroxide, T between 900º e 1200ºC; group 3 - quartz, clay minerals (probably kaolinite), calcite and/or dolomite, iron oxide or hydroxide, and T between 1200º e 1565º C.
Acesso aberto (Open Access)
Intemperismo tropical em fachadas azulejadas de edificacoes historicas em belem do para
(Universidade Federal do Pará, 2007-05-14) SANJAD, Thais Alessandra Bastos Caminha; COSTA, Marcondes Lima da; http://lattes.cnpq.br/1639498384851302
The application of European tiles on building façades of Belém city started since 19th century. After hundred years under weathering action, the tiles started to show alterations. To understand these weathering action two historical buildings of the 19th century were studied: Palacete Pinho and Solar do Barão de Guajará, located on Belém old town. The Palacete building has German tiles (PPA and PPA-C) and Portuguese tiles from Porto city (PPP). The Solar building has only Portuguese tiles on its main façade, from Porto city (BGFP). Dark stains are the main kind of alteration found in the German tiles. They are located between the glaze and the ceramic part, without lost of glaze. In case of the Portuguese tiles from both buildings, the lost of glaze is frequent, besides the presence of green stains under the detached glaze. Physical characterization results are as follow: 1) the German tiles (PPA and PPA-C) have a lower accessible porosity (12.96% and 9.59%, respectively) and higher density (1.99 g/cm3 and 1.92g/cm3, respectively), than the Portuguese ones (PPP: 29.34% and 1.59 g/cm3 and BGFP: 17.53% and 1.74 g/cm3); 2) the Portuguese tiles present glaze thickness between 0.06-0.1 mm (PPP) and 0.5-0.54 (BGFP) and the German ones between 0.04-0.2 mm (PPA and PPA-C); 3) Portuguese glazes exhibit an abrupt contact with the ceramic part while German tiles show a transition zone between these two layers. Mineralogical analyses of the ceramic parts were carried out using XRD and SEM/EDS. The main mineral phases identified are: quartz, mullite, and cristobalite (German tiles) and quartz, gehlenite, diopside and calcite (Portuguese tiles). Quartz, cassiterite and apatite were also found in both German and Portuguese glazes; only the PPP sample does not have cassiterite. Total chemical analyses of the ceramic parts of German tiles indicated a major amount of SiO2 (75%) and Al2O3 (18%). In the Portuguese tiles, besides SiO2 (46%) and Al2O3 (15%), there is also high CaO contents (22%). Concerning the glazes, the chemical composition is mainly composed by Si and Pb. The green and dark stains beneath the glaze are related to microorganisms of the Cyanophyta and Bacillariophyta divisions. Climatic data records from Belém city were recovered since 1898 and showed that no significant climate changes happened in the region. Rain water sampling and analysis were also carried out in the vicinities of the two studied buildings. 11 The results show small Ca concentrations above regular levels for rain water, which can be related to the mortars. The temperature measurements on tile surfaces indicate variations for different parts of the façades. In the Solar Building, areas of high surface temperature are those where the glaze was unattached to the ceramic bodies. The results showed that the tiles are rather resistance to the tropical weathering. German tiles have a minor glaze lost because of the interface zone between glaze and ceramic part. The absence of such zone in the Portuguese tiles turn then more prone to weathering due to climate changes, mainly thermal daily variations, which lead to glaze detachment.
Acesso aberto (Open Access)
Potencialidade das assinaturas isotópicas de Pb por espectrometria de massa ICP-MS e TIMS no estudo da proveniência dos azulejos das fachadas históricas de Belém, PA
(Universidade Federal do Pará, 2010-04-13) OLIVEIRA, Etiana Costa; LAFON, Jean Michel; http://lattes.cnpq.br/4507815620234645
Since the eighteenth century, frontages of old buildings from the city of Belem and others Brazilian cities like Salvador, Recife, Rio de Janeiro and São Luis, have been covered with tiles imported principally from Portugal and from others countries of Western Europe, constituting and valorous historical patrimony. The purpose of this study is to evaluate the potentiality of Pb isotopes as a tool for the identification of the provenience of the tiles of historical building from Belem by lead isotope analyses of the tile’s glaze compared with possible Pb ores deposits sources in Western Europe. The study included a comparison of Pb isotopic results obtained by Thermo-ionization mass spectrometry (TIMS) and ICP- mass spectrometry (ICP-MS) on a Finnigan MAT 262 mass spectrometer and a Thermo-Finnigan Neptune ICP-MS mass spectrometer, respectively. Pb isotopes were determined on 36 samples of tiles (23 tiles from Portugal, 5 tiles from England, 4 tiles from France, 4 from Germany). Six samples of tile from the city of São Luis an of unknowm origin , including from de seventeen century, 4 from the eighteenth century and from nineteenth century were also investigated. Additionaly, Pb isotope analyses were also performed on 8 samples of Brazilian modern tiles to evaluate possible distinction between isotopic signature of original European tiles and national replications. A compilation of isotopic signatures of the main Pb deposits in Western Europe and Brazil was necessary in order to compare the Pb isotope compositions of the deposits and tiles. According to the chemical composition and, principally, the high Pb contents of the glaze a simple analytical procedure by HF leaching was adopted for Pb extraction of the glaze, without chemical separation and purification by ion-exchange chromatography. The measurements of Pb isotopic composition by TIMS and ICP-MS on the same samples displayed some differences but these differences do not affect the interpretations of the results. The 208Pb/206Pb vs. 207Pb/206Pb diagram is shown to be the most helpful for the discussion of the Pb isotopic signatures. When comparing with the field of isotopic signatures of Western Europe deposits as probable source of the Pb of the glazes, isotopic compositions indicate that no direct relationship can be established between the country of fabrication of the tile and the country of production of the Pb. Almost the countries from Western Europe may have furnished glaze’s lead. However, Spain (Alcudia Valley), England / Whales and, probably, France have been the main furnishers. Lead produced by the Portuguese deposits and the Cartagena deposits in Spain were not used for the fabrication of the historical study tiles. The similarities in age and geological context of the Pb ore deposits from Western Europe provoked an overlap between the Pb isotopes fields from several countries, making difficult to distinguish the Pb provenience, principally for England, France, Germany and Belgium. Others factors like overlapping of the Pb isotopic signatures produced by different countries, evidences of Pb mixing from several deposits used for the tile fabrication and the lack of confident historical informations about Pb mining and trading in Western Europe, also limited the use of Pb isotopic composition from the tile provenience. Despite these limitations, this study permitted to identify a specific and homogeneous Pb isotopic signature for the older tiles, made before the nineteenth century. It has been also possible to point out the utilization of Pb imported from other continents for the fabrication of some Portuguese, English and German tiles at the end of 19th century or the beginning of the 20th century which is in good agreement with the declining of Pb mining in western Europe during the second half of the 19th century. Portuguese tiles displayed a roughly homogeneous Pb isotope signature depending on the furnisher as well as distinct Pb signatures from furnisher to another one. Then a refining of the study on the base of a larger set of European tiles would possibly be able to be used as a helpful tool for determination of the age and maker of the tiles covering the frontage of historical buildings in Brazil. Finally, this study indicated that Pb used for the fabrication of modern Brazilian tiles and replications of historical tiles of the city of São Luis came from a mixture of Pb from the State of Bahia (Boquira and Nova Redenção deposits). The overlapping of some of the Brazilian modern samples with the field of Western Europe lead deposits and with some of the historical tiles from Western Europe restrain the capability for Pb isotope signature to be employed for distinction between modern and historical tiles.