Preserving and analytically examining daguerreotypes is particularly challenging because of their multi-material and multi-component structure. Various sensors have been exploited to examine mainly the image plates of the daguerreotypes even though the degradation goes beyond this component. Micro-analyses have been the preferred method due to the nanoscale structure of the image particles. In this work, we propose comprehensive multi-modal non-invasive sensing to investigate the corrosion products present in nine daguerreotypes from the Fondazione Alinari per la Fotografia (FAF, Florence, Italy). The methodology proposed includes chemical and morphological analyses: portable X-ray fluorescence spectrometry (pXRF), Raman microspectroscopy (μ-Raman), and micro-Fourier transform infrared spectroscopy in reflection mode (μ-rFTIR) for the chemical identification. For the first time, optical coherence tomography (OCT) was deployed to record the cross-sectional and morphological data of the relevant corrosion formations on daguerreotypes in a contactless way. The results allowed the characterization, in a non-invasive mode at a microscopic level, of a wide range of degradation products produced by the interaction of the different elements present in the structure of the daguerreotypes. The aim was to verify the performance of the proposed methodology and to link the chemical and physical complexity of the entire structure, disclosed by the state-of-art sensors, to the daguerreotype degradation. The results draw attention to the need to monitor not only the image condition but the whole object as a partially closed system in constant interaction internally and with the environment.

The public expected color from the early photographic images, yet, daguerreotypes—the first commercially available photographic process—failed to register the natural colors. Daguerreotypists developed several coloring methods to solve this inconvenience after 1840. Scientific analyses of the hand-colored daguerreotypes are limited, and the primary information sources available are manuals and patents. This study aims to contribute to the knowledge of hand-coloring techniques, which impacts conservation practices, mainly the cleaning procedures and complements technical art history investigations. We studied nine colored daguerreotypes with a non-invasive methodology based on three spectroscopic techniques: X-ray fluorescence (XRF), micro-Raman spectroscopy (μ-Raman), and micro-Fourier-transform infrared spectroscopy in reflection mode (μ-rFTIR). The results revealed the different colorants and some of their mixtures employed by the colorist. It also adds information regarding the photographic production of three studios: Désiré François Millet, active in Paris between 1840 and 1868; Antoine Claudet (1797–1867), active in London; and the James E. McClees and Washington Lafayette Germon studio, operative between 1846 and 1855 in Philadelphia, USA. These technical details constitute a helpful comparison to future studies on Daguerreian studios and colored daguerreotypes.

This paper deals with the study of organic coatings (patinas) on historical bronzes, specifically those applied on small-size statues in Renaissance workshops. These coatings, often transparent and translucent, contain a mixture of organic and inorganic components and may be still preserved in hidden parts of statues in indoor displays. However, the complexity of the original varnishes, their degradation and alteration over time, and the coexistence of materials added for conservation and maintenance purposes are challenging for their characterization. The often well-preserved surface of varnished bronzes and their small size make it mandatory to make the most of using noninvasive techniques for their investigation. To this end, to simulate the actual historical coatings, we prepared a set of mock-ups following ancient recipes and using materials that were available in the Renaissance. We used the samples to assess to what extent it is possible to disclose the formulation (binders, colourants, and other additives) and the thickness of a Renaissance patina with noninvasive methods. Microprofilometry (MP), optical coherence tomography (OCT), and eddy current (EC) gauge were tested on the samples and the results were combined with reflectance Fourier transform infrared (FT-IR) spectroscopy. The analyses performed on the mock-ups set the ground for investigating a Renaissance bronze featuring reddish semi-transparent varnish layers. The achievements are discussed in this paper, along with the limitations of the use of a noninvasive approach.

This study investigates the application of Life Cycle Assessment (LCA) as a tool to evaluate the environmental performance of innovative methodologies in cultural heritage conservation. Three categories of restoration treatments were analyzed: disinfection of stone surfaces, consolidation of degraded organic materials, and dry cleaning of metal surfaces. For each category, experimental or alternative conservation solutions were compared with conventional commercial or artificial products, focusing exclusively on environmental impacts rather than technical performance. The results highlight significant variability across treatments. In stone disinfection, the biological approach based on Serratia ficaria SH7 shows a substantially lower environmental impact compared to the synthetic biocide Preventol RI50. In contrast, the consolidation scenario reveals a more complex pattern: crystalline nanocellulose demonstrates low impacts when water-based, but its environmental performance worsens considerably when organic solvents are used, in some cases exceeding that of the synthetic resin Plexisol P550. For dry cleaning, all tested eraser formulations exhibit relatively low impacts, although silicone-based systems outperform latex-based alternatives due to reduced material consumption. Beyond comparative results, the study critically examines methodological limitations of LCA in conservation contexts, including data asymmetry between laboratory-scale and industrial processes, sensitivity to modelling assumptions, and restricted system boundaries. The findings demonstrate that environmental performance depends not only on material origin but also on formulation, energy use, and operational conditions. Overall, LCA proves to be a valuable but context-dependent decision-support tool, requiring transparent assumptions and careful interpretation to effectively guide sustainable practices in cultural heritage conservation.

This chapter illustrates the potential of using volatile binding media (VBM) in emergency contexts to secure works of art through a temporary consolidation that allows either a safe transport or an in-situ restoration. VBM are substances with adhesive and cohesive properties that at room temperature are solid, passing directly to the aeriform state by sublimation. They are requested to ensure adequate consolidation, to leave the composition, morphology, or structure of the object unaffected, and to be completely reversible. Cyclododecane (CDD) was extensively used in past decades, but, due to its recent limited availability, the identification of an alternative VBM is a challenging task. In this work, experimental activity focuses on characterizing the properties of either already known molecules (such as menthol) or less investigated materials (such as menthyl lactate). The application of VBM (melted or dissolved in solvents) on several substrates (wood, plaster, terracotta…) was explored to evaluate different parameters. These results will be useful to select the most adequate application protocol in different emergency contexts. Preliminary results of the use of the selected VBM on a wooden sculpture recovered after the 2016 earthquake are reported. Biocide activity of menthol, as a further property to secure artworks, was also studied.