ALCOBAÇA'S ABBEY GLAZED TILES COLOUR PALLETE
The pavement of the apse of the Alcobaça’s Abbey was originally decorated using monochromatic glazed tiles combined in several colours and geometric shapes. The performed analytical work involved the determination of the glazed tiles chemical composition responsible for the observed colours (white, turquoise, brown and several shades of green). Results show that tin-opacified lead glazes were used which constitutes the first known example (13th century) of this type of production in Portugal and reveals the influence of the Islamic tile technology. The colour palette was found to be obtained from the combination of different proportions of CuO, Fe2O3 and SnO2 in a lead-glazed matrix although only for the white and turquoise colours the content of SnO2 was superior to 10 wt%. A K-feldspar-rich white layer was also used between the ceramic body and the glaze then allowing to obtain more vivid colours.
This work results from the strong collaboration maintained with VICARTE - Dept. of Conservation and Restoration from UNL, focused on the characterization of historical glasses, stained glasses and tiles. Some of these works are listed below.
Luís Cerqueira Alves
Carvalho, F., Coentro, S., Costeira, I., Trindade, R.A.A., Alves, L.C., Silva, R.C., Muralha, V.S.F. (2016) The Cistercian glazed tiles of the Monastery of Alcobaça: characterization of the colour palette, Journal of Medieval Iberian Studies, 8:2, 196-216, http://dx.doi.org/10.1080/17546559.2016.1222447
Coutinho, I., Berger, F., Rodrigues, A., Coutinho, M., Machado, A., Alves, Luis C., Vilarigues, M., Fensterbierscheiben in the Pena National Palace collection – chemical and iconographic relations, X-Ray Spectrom 45 (2016) 308-317, http://dx.doi.org/10.1002/xrs.2706
Coutinho, M. L., Veiga, J. P., Alves, L. C., Mirão, J., Dias, L., Lima, A. M., Muralha, V. S., Macedo, M. F., Characterization of the glaze and in-glaze pigments of the nineteenth-century relief tiles from the Pena National Palace, Sintra, Portugal, App. Phys. A (2016) 122:696, http://dx.doi.org/10.1007/s00339-016-0214-5
Coutinho, I; Medici, T.; Alves, L.C.; Gratuze, B.; Vilarigues, M., Provenance studies on façon-de-Venise glass excavated in Portugal, Journal of Archaeological Science: Reports, 7 (2016) 437–448 http://dx.doi.org/10.1016/j.jasrep.2016.03.019