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Highlights • 44 ancient gypsum-based plasters belonging to 3 types of elements were analysed. • Physical and mechanical properties are presented and related to application techniques. • Different porosity features were found for each type of plaster element. • The moulded on site elements had the highest water absorption characteristics. • Higher gypsum content led to higher mechanical performance. Abstract The study of the physical and mechanical properties of 44 ancient gypsum-based plaster samples is the base for the design of compatible solutions to be used in restoration and conservation interventions. Three types of plaster elements – thin-layer, moulded on site and pre-moulded – were analysed. The results show a relation between composition and application technique. Different porosity features were found for each type of plaster element. Moulded on site elements have the highest water absorption characteristics, and thin-layer samples have the lowest. Mechanical properties could also be related with composition: higher gypsum content leads to higher compressive strength and higher ultra-sound pulse velocity. Based on this data, the quantitative requirements for the development of compatible restoration products were established. [ABSTRACT FROM AUTHOR]

Highlights • Four fungal species cause deterioration on the stuccoed vault of a heritage building. • Morphological identifications are improved by molecular analyses on fungal isolates. • Species-specific sensitivity is recognizable for most of assayed biocide treatments. • Most of assayed consolidants stimulate the growth of the detected species. • Species-specific assays are necessary to address the use of restoration products. Abstract Investigations are needed to address and optimize the use of biocides and restoration materials with reference to the fungal diversity, which often characterizes cultural heritage surfaces. This work aimed to examine the diversity of fungi responsible of aesthetic decay on the stuccos of the vault of a religious building in Torino (NW-Italy), and to evaluate the sensitivity of the detected set of species to widely used biocidal products (benzalkonium chloride, isothiazolinones, sulphamide derivatives) and their application solvents. The effect of four commercial consolidants on their potential (re-)colonization following restoration interventions was also assessed. Four different deterioration phenomena were related to the occurrence of Chaetomium murale , Stachybotrys chartarum , Penicillium chrysogenum and Sarocladium kiliense , respectively. Surface receptivity to the different species – identified on morphological and molecular bases – was related to slightly different thermo-hygrometric conditions, the distribution of painted surfaces, salts, and local remnants of cellulose poultice used in past restoration interventions. Specific sensitivity to two solvents and ten different biocide treatments was evaluated in terms of inhibition of mycelial growth from transplanted inocula at 9 (T1) and 27 (T2) days after the incubation. The different solvents and biocide products differently affected growth and/or pigmentation of the four species. Only 40% of the ten performed biocide treatments determined the growth inhibition of all the examined species at both T1 and T2. In other cases, inhibition observed at T1 for C. murorum , S. chartharum and S. kiliense , was followed at T2 by the colonization of inhibition zones. The mycelial growth on an oligotrophic culture medium poured with four commercial consolidants was evaluated one year after the incubation. All the species displayed some growth from the inocula, with a scarce biomass being only observed in negative (water) controls and upon one consolidant treatment. The three other products strongly supported a higher growth of at least two of the examined fungal species with respect to negative controls. In conclusion, different sensitivity of each fungal species for most biocidal treatments and stimulation by consolidants indicate that species-specific assays of products are necessary to calibrate and optimize restoration works. In particular, effective inhibition of fungi by biocides, and potential stimulation by consolidants, should be evaluated after several weeks and months, respectively, since short-term monitoring may be misleading. [ABSTRACT FROM AUTHOR]

In this paper, chemical and structural studies of medieval wall paintings in Ocre (L’Aquila, Italy) are presented. During the latest restoration campaign, non-destructive (Near-Infrared Reflectography and Infrared Thermography) and micro-invasive (Nuclear Magnetic Resonance, Fourier Transform Infrared Spectroscopy, μ-Raman, Scanning Electron Microscopy with X-ray Microanalysis, X-Ray Diffraction, X-Ray Fluorescence, Optical Microscopy, Mass Spectrometry, Thermogravimetry) analyses were performed in order to determine the detachments of wall surfaces and the characterization of original and restoration materials. Data integration allowed to reconstruct the conservative history, the execution techniques and the conservation problems of the artefact, as well as to assess the effectiveness of restoration activities adopted. The combined use of physical and micro-chemical techniques proved to be effective for an in-depth study of materials stratification of paintings. [ABSTRACT FROM AUTHOR]

Abstract: During one of Coronelli''s terrestrial globes restoration, belonging to the Bologna University, we found some substances considered not to be original. Their presence was both on the globe surface and under one of the gores. In order to characterise the organic material (original or added in restoring procedures) we employed pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The analytical results reveal the presence of the original materials, such as natural gums and animal glues, together with industrial products, such as synthetic germicides. [Copyright &y& Elsevier]