A multi-analytical approach was used to study the pictorial layers of a set of 17th century historic glazed tiles (azulejos) of Portuguese manufacture. The pictorial layer was studied by-EDXRF,-Raman, SEM-EDS and OM. Although the established palette comprises few pigments, it was found that the tiles were enhanced by the use of pigment mixtures, which were identified by-Raman and-EDXRF. As expected, the blue colour derives from cobalt oxide, purple from manganese oxide and emerald-green from copper oxide. Regarding the yellow pigment,-Raman results show it is consistent with the composition of a ternary oxide, whereas-EDXRF shows a high intensity of Zn in this colour, indicating a composition close to a Pb-Sb-Zn ternary oxide. Some compounds from the original ores were also indentified: in two very dark blue samples, cobalt and nickel olivines (␣-Co 2 SiO 4 , ␣-Ni 2 SiO 4), and in a dark brown sample, braunite (a manganese silicate).

The Fishing House located on the grounds of the Marquis of Pombal Palace, Oeiras, Portugal, was built in the 18th century. During this epoch, Portuguese gardens, such as the one surrounding the Fishing House, were commonly ornamented with glazed wall tile claddings. Currently, some of these outdoor tile panels are covered with dark colored biofilms, contributing to undesirable aesthetic changes and eventually inducing chemical and physical damage to the tile surfaces. Phylogenetic analyses revealed that the investigated biofilms are mainly composed of green algae, cyanobacteria and dematiaceous fungi. With the aim of mitigating biodeterioration, four different biocides (TiO nanoparticles, Biotin T, Preventol RI 80 and Albilex Biostat ) were applied in situ to the glazed wall tiles. Their efficacy was monitored by visual examination, epifluorescence microscopy and DNA-based analysis. Significant changes in the microbial community composition were observed 4 months after treatment with Preventol RI 80 and Biotin T. Although the original community was inactivated after these treatments, an early stage of re-colonization was detected 6 months after the biocide application. TiO nanoparticles showed promising results due to their self-cleaning effect, causing the detachment of the biofilm from the tile surface, which remained clean 6 and even 24 months after biocide application. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

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The presence of uranium glass objects in museum and private collections has raised radiation protection concerns resulting from possible exposure to ionizing radiation emitted by this type of object. Fourteen glass objects with different uranium contents were studied. Dose rates (b þ g radiation) were measured with a beta/gamma probe at several distances from the glass objects. In general, the determined dose rates did not raise any concern as long as some precautions were taken. Radon ( 222 Rn), usually the most important contributor for the overall natural dose exposure resulting from radium ( 226 Ra) decay in the uranium natural series, was also evaluated and it was found to be within the background values. Non-invasive analyses of the uranium content were made using micro-EDXRF analysis, measuring the radiation emitted by the objects and fluorescence spectroscopy.

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