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The paint coatings of three energy generators from the 20th‐century powerplant at Levada de Tomar, Portugal, were investigated using micro‐Raman and micro‐X‐ray fluorescence spectroscopies and scanning electron microscopy with energy dispersive spectroscopy. This multi‐analytical approach was used to identify the colouring agents, thus providing a chronological chromatic pallet and allowing to infer on the use of the three energy generators. Together with traditional pigments like Prussian blue, red iron oxide, and carbon black, pigments used in industrial areas like copper phthalocyanine and toluidine red were identified as colouring agents. Complex paint systems of the oldest equipment (1924) were revealed as well as maintenance procedures of the equipment that worked during a longer time (1944–1990). Powdery carbon black layers, resulting from incomplete hydrocarbon combustion and present between metallic substrates and coating layers, suggested the inexistence of paint coatings replacement after the powerplant shutdown. The identification of magnetite as a corrosion product of iron alloy substrate revealed that corrosion developed after the engine shutdown and not during the operation period. The results obtained highlight the potentialities of scientific‐based approach and Raman spectroscopy to the industrial heritage study, an emergent cultural area.

The permanent exhibition “Treasures of Portuguese Archaeology” of the Portuguese National Archaeological Museum is composed mainly of gold and silver artefacts which present extensive surface corrosion. The construction of the exhibition room dates from the late 1980s, and it was conceived with the highest security standards in mind. However, at that time, the importance of the choice of compatible materials and equipments for the exhibition of metal artefacts was still unknown, and the same was true for the influence in terms of corrosion development, even for gold objects, if an inappropriate material was selected. Preventive conservation directives and actions have been developed since then, and presently one is confronted with new paradigms for the exhibition and preservation of artefacts, and, moreover, of cultural heritage. A preventive conservation project, which is currently in its initial stages, was set up with the objective of identifying and understanding the pathologies observed, in order to correct the problems presented by the exhibition room. This article presents an overall view of the project, a description of the alterations observed, and a summary of the methods proposed for obtaining responses to the respective problems, with the purpose of correcting the room’s fragilities.