Recovery of the traditional colours of painted woodwork in the Historical Centre of Lugo (NW Spain)

The rehabilitation of the degraded medieval quarter of A. Tineria, in Lugo (NW Spain) included the recovery of the traditional colours on plasters and woodwork. To achieve this aim, the paint materials on wooden elements (window frames and doors) have been characterised firstly by means of colour measurements on site, with a portable solid reflection spectrophotometer, and secondly by pigment analysis of paint samples, using OM, SEM-EDS and MRS. The results revealed that the predominant colour in the cityscape of the 19th and early 20th century was red, and that the paints contained red ochre of a local origin, in some cases with the addition of red lead. Other minor colours were identified as well: blue paints contained ultramarine blue or Prussian blue, yellow paints contained lead oxide and green paints were based on copper pigments or on a mixture of Prussian blue and yellow lead oxide. Extenders like barium sulfate, gypsum or calcite were often added to the paints. Finally, the turquoise paints were applied in recent times, as titanium white and phtalocyanine green (both industrially synthesised in the 20th century) were identified in their composition. These results have contributed to the elaboration of the Colour Plan of the Historic Centre of Lugo. The rehabilitation of A. Tineria is still ongoing and has received one of the United Nations' International Dubai awards in 2008, recognizing good practices and local leadership. (C) 2011 Elsevier Masson SAS. All rights reserved.