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Sobre os materiais utilizados na talha da época barroca do noroeste de Portugal -primeiros resultados

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Resumo Com o objectivo de contribuir para o conhecimento da talha portuguesa do período barroco apresentam-se os primeiros resultados de um estudo de 18 retábulos pertencentes à cidade do Porto. Pretendeu-se identificar os materiais e as técnicas usadas nas camadas de gesso, de bolo e de douramento, usando microscopia óptica e microscopia electrónica de varrimento. Identificou-se anidrite e gesso com baixo teor de impurezas, bolo de boa quali-dade e ligas metálicas com concentração de ouro quase sempre superior a 90%. Os dados obtidos até ao momento sugerem que as recomendações dos docu-mentos da época terão sido seguidas na maioria dos casos. Palavras-chave: Retábulo; talha dourada; gesso; bolo; folha de ouro; microsco-pia óptica; microscopia electrónica de varrimento. Abstract Aiming to contribute to the knowledge of Portuguese gilded wood from the Baroque, the first results of a study of 18 retables belonging to Oporto are presented. In order to identify the materials and the techniques used in gesso, bole and gold leaf layers, optical microscopy and scanning electron microscopy were used. Anhydrite and gypsum with low concentration of impurities, bole of good qua-lity and gold alloys with a concentration of gold usually above 90% were iden-tified. The results suggest that recommendations found in historical documents have been followed in the majority of the cases.
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... Thus, by using on-line gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) and by comparison with modern reference fats, researchers can now distinguish different animal fats (dairy and several ruminant and non-ruminant species) by plotting the 13 C value for palmitic acid against that for stearic acid [15,16]. Using the available analytical methodologies, researchers have identified several commodities used during the Neolithic period in different parts of the world, including milk [17][18][19][20][21][22][23], animal fat [24,25], fish [26], and resins [27,28]. ...
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... The studies that have been published on the organic content of Neolithic ceramics have been done on materials excavated in settlement sites [17][18][19][20][21][22][23][24][25][26][27][28], while the Zambujeiro ceramics come from a funerary context. ...
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... Thus, by using on-line gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) and by comparison with modern reference fats, researchers can now distinguish different animal fats (dairy and several ruminant and non-ruminant species) by plotting the 13 C value for palmitic acid against that for stearic acid [15,16]. Using the available analytical methodologies, researchers have identified several commodities used during the Neolithic period in different parts of the world, including milk [17][18][19][20][21][22][23], animal fat [24,25], fish [26], and resins [27,28]. ...
... GC-MS is a separation technique that allows the identification of the organic compounds present in the ceramic samples. The sample preparation included the previous cleaning of the ceramic to eliminate handling contamination, sample collection, extraction with a chloroform/ methanol mixture, derivatization with N,O-Bis(trimethylsilyl) trifluoroacetamide + 1% trimethylchlorosilane (BSTFA) [28] and further injection in the GC-MS system. ...
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Costa, J. R. Graça. O gesso em Portugal. In: Estudos, Notas e Trabalhos. Lisboa: Direcção Geral de Geologia e Minas. Vol. 28 (1986), pp. 93-117.
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  • Maria Cardoso
  • F P Isabel
Cardoso, Maria Isabel Isabel F. P. 18th century altarpieces in Algarve, Portugal: a comparison of the historical documents to the results of the microscopical analysis. In: Infocus. Vol. 41 (4) (2001), pp. 64-86
Le Retable Majeur de la Sé Velha de Coimbra et la Polychromie dans la Diocèse de Coimbra à l'époque Barroque
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Le Gac Arinto, Agnès Anne Françoise. Le Retable Majeur de la Sé Velha de Coimbra et la Polychromie dans la Diocèse de Coimbra à l'époque Barroque. Aspects Techniques et Estétiques. Tese de doutoramento, Lisboa: Universidade Nova de Lisboa (2009).
potencialidades e avaliação do gesso do depósito de São José do Pinheiro
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  • Caracterização
Campos, Carlos M. D. Caracterização, potencialidades e avaliação do gesso do depósito de São José do Pinheiro (Soure, Portugal). Tese de mestrado defendida em 2002 no Departamento de Geociências da Universidade de Aveiro.