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The Hebrew Scroll, catalogued as Magliabekian Manuscript III 43 and belonging to the National Central Library of Florence (BNCF), is a membranous richly decorated scroll, with colorful depictions of sacred sites through the Holy Land to Lebanon along with handwritten texts in Hebrew and notes in Italian. Despite the fact that the manuscript was originally catalogued as an "object of no artistic or scientific value", recent paleographic studies dated it to the XIV century and highlighted it as the oldest scroll still available, depicting holy places from Egypt to Lebanon. Nevertheless, precise dating, authorship, and the interpretation of its original function are still uncertain. A suite of complementary techniques was used, including photographic documentation in visible (VIS) light in diffuse light, grazing light, and transillumination, luminescence induced by ultraviolet (UV) radiation, imaging spectroscopy (IS), Macro Area X-ray Fluorescence (MA-XRF), and spot analyses such as fiber-optic reflectance spectroscopy (FORS) in the UV, VIS, and near-infrared (NIR) regions, Fourier transform infrared spectroscopy (FT-IR) in external reflectance mode (ER), and micro-Raman spectroscopy. The results of the non-invasive diagnostic campaign enabled the identification of several constituting materials (parchment, pigments, binder, and inks). The identified materials were consistent with the proposed dating and geographical manufacturing area of the artefact. [ABSTRACT FROM AUTHOR]

• Imaging spectroscopy discloses the secrets of Picasso's painting "La Copa Blava". • Reflectance hyperspectral imaging enabled visualisation of earlier versions of the painting. • New-insights on the Picasso Blue period are gained with imaging spectroscopy. • Reflectance hyperspectral imaging has a potential for museums educational tasks. Reflectance hyperspectral imaging (HSI) in the Visible and Near-IR (VNIR) to the Short Wave IR (SWIR) ranges is acknowledged as one of the most effective techniques for non-invasive examination of paintings. Recently, in some important museums worldwide a new trend has emerged towards a more systematic use of reflectance HSI, which is applied as advanced imaging technique to attain at once analysis and documentation of the painted surfaces and inner layers. As an example of this trend, in the framework of the interdisciplinary program "Picasso: Blue Project" recently carried out at the Museu Picasso in Barcelona, a selection of paintings of the Blue Period (1901–1904) collection were revisited through the eye of cutting-edge analytical techniques, including reflectance HSI. The present paper focuses on the painting "The Blue Glass" (La Copa Blava, 1903), which was examined by using a high-performance reflectance HSI instrumentation. Under its visible surface, this iconic oil on canvas featured a stratification of different compositions that perfectly witnessed the Picasso's creative process. The HSI data enabled an unprecedented visualisation of the artistic metamorphosis of this painting. The well-known Picasso's creative practice of repainting on his own canvas was brought to the light by means of HSI images, which offered unique materials for visualising the hidden layers of the painting, by disclosing subsequent and unknown earlier versions and the artistic evolution of the painting. The outcomes of the project were disseminated in an exhibition, that addressed the ambitious objective of sharing with the wide public scholarly advanced knowledge hitherto gained on the Picasso Blue Period. Within this context, reflectance HSI proved to be exceptionally effective, not only for addressing analytical tasks, but also for educational purposes. [ABSTRACT FROM AUTHOR]

Conspectus: Diffuse reflectance hyperspectral imaging, or reflectance imaging spectroscopy, is a sophisticated technique that enables the capture of hundreds of images in contiguous narrow spectral bands (bandwidth < 10 nm), typically in the visible (Vis, 400-750 nm) and the near-infrared (NIR, 750-2500 nm) regions. This sequence of images provides a data set that is called an image-cube or file-cube. Two dimensions of the image-cube are the spatial dimensions of the scene, and the third dimension is the wavelength. In this way, each spatial pixel in the image has an associated reflectance spectrum. This "big data" image-cube allows for the mining of artists' materials and mapping their distribution across the surface of a work of art. Reflectance hyperspectral imaging, introduced in the 1980s by Goetz and co-workers, led to a revolution in the field of remote sensing of the earth and near planets. In the subsequent decades, thanks to rapid advances in solid-state sensor technology, reflectance hyperspectral imaging, once only available to large government laboratories, was extended to new fields of application, such as monitoring agri-foods, pharmaceutical products, the environment, and cultural heritage. In the 2000s, the potential of this noninvasive technology for the study of artworks became evident and, consequently, the methodology is becoming more widely used in the art conservation science field. Typically hyperspectral reflectance image-cubes contain millions of spectra. Many of these spectra are similar, making the reduction of the data set size an important first step. Thus, image-processing tools based on multivariate techniques, such as principal component analysis (PCA), automated classification methods, or expert knowledge systems, that search for known spectral features are often applied. These algorithms seek to reduce the large number of high-quality spectra to a common subset, which allow identifying and mapping artists' materials and alteration products. Hence, reflectance hyperspectral imaging is finding its place as the starting point to find sites on polychrome surfaces for spot analytical techniques, such as X-ray fluorescence, Raman spectroscopy, and Fourier transform infrared spectroscopy. Reflectance hyperspectral imaging can also provide image products that are a mainstay in the art conservation field, such as color-accurate images, broadband near-infrared images, and false-color products. This Account reports on the research activity carried out by two research groups, one at the "Nello Carrara" Institute of Applied Physics of the Italian National Research Council (IFAC-CNR) in Florence and the other at the National Gallery of Art (NGA) in Washington, D.C. Both groups have conducted parallel research, with frequent interchanges, to develop multispectral and hyperspectral imaging systems to study works of art. In the past decade, they have designed and experimented with some of the earliest spectral imaging prototypes for museum applications. In this Account, a brief presentation of the hyperspectral sensor systems is given with case studies showing how reflectance hyperspectral imaging is answering key questions in cultural heritage. [ABSTRACT FROM AUTHOR]

Abstract: Fibre Optics Reflectance Spectroscopy (FORS) is a well-established technique, widely used in the conservation field for in situ investigations and non-invasive diagnostics on traditional artworks. Nevertheless, there is little knowledge on the use of this technique for investigating modern artists materials used in contemporary artworks. The present study, carried out within the wider framework of the EC funded Project “POPART” (Preservation of Plastic ARTefacts in museum collections”), was aimed at investigating the possibility of extending the applications of FORS to synthetic polymers, and proposing this technique as new non-invasive analytical tool for diagnostics on plastic artworks in museum collections. Thus, a real case was selected from the permanent collection of the Conteporary Art Centre “Luigi Pecci” (Prato, Italy). The artwork, created in 1990 by the artist Stefano Arienti, was entirely constituted of expanded polystyrene (EPS) and it showed diffused signs of degradation. The need of singling out the main causes of deterioration in order to prevent further damages was evident. An in situ FORS measurements campaign was performed with the aim of gaining in-depth information about its conservation state and identifying the main agents responsible for the observed degradation. Thanks to the non-invasivity of the technique an extensive spectroscopic characterisation of different areas of the EPS surface could be performed and the spectral data were exploited to build a map of the degraded areas of the artwork. Data acquired in field were compared with those obtained from laboratory test performed on artificially aged EPS samples. These results helped in ascertaining the detrimental actions of the light sources used to back illuminate the artwork. In particular, in this case FORS proved to be effective in detecting EPS alterations before the chromatic effects became visually evident. These results suggested that FORS may be considered as a good candidate to be used for non-invasive investigations also on some modern materials and contemporary artworks. The research was completed with an interview to the artist Stefano Arienti, whose point of view was constructively integrated with the scientific results obtained. This emphasized the importance of an interdisciplinary approach to the solution of conservative problem in the field of contemporary art. [Copyright &y& Elsevier]

Fiber optics reflectance spectroscopy (FORS) and visible and near-infrared (VNIR) hyperspectral imaging (HSI) were applied to assess and control the laser cleaning process of a deeply darkened limestone surface collected from the historic entrance gate of Castello Svevo, Bari, Italy. Both techniques enabled us to verify the different degree of removal of a thick deposit of black crust from the surface of the walls. Results obtained were in good agreement with those of previous studies of the elemental composition achieved by application of laser-induced breakdown spectroscopy (LIBS). Coupling FORS and VNIR-HSI provided important information on the optimal conditions to evaluate the conservation status and determine the more appropriate level of cleaning restoration, thus avoiding over- and/or under-cleaning. Imaging spectroscopy was used to obtain maps of areas featuring the same or different spectral characteristics, so to achieve a sufficient removal of unwanted layers, without modifying the surface underneath, and to increase the efficiency of traditional cleaning techniques. The performance of the combined non-invasive approach used in this work shows promise for further applications to other types of rocks and highlights the potential for in situ assessment of the laser cleaning process based on reflectance spectroscopy. [ABSTRACT FROM AUTHOR]

In the occasion of the celebrations for the 150th anniversary of the founding of Italy (1861–2011), it was decided to analyse the artwork “ The Italian Flag ” ( La Bandiera Italiana ) created by the artist Fernando Melani (Pistoia, 1907–1985), one of the precursors of the Poor Art artistic movement in Italy. This project is a follow-up to a previous study which was mainly focused on the pigments and dyes found in his home-studio. The main goal of this paper is to identify a correct diagnostic plan, based on the use of a combination of non-invasive and micro-invasive methodologies, in order to determine the state of preservation and define the best conservation procedures for a contemporary artwork. Visible, infrared and infrared false colour images as well as the Fibre Optic Reflectance Spectroscopy (FORS) technique were applied in situ to analyse The Italian Flag . Laser Induced Breakdown Spectroscopy (LIBS), Fourier Transform Infrared (FT-IR) and micro-Raman spectroscopies, Pyrolysis-Gas Chromatography/Mass Spectroscopy (Py-GC/MS), High Performance Liquid Chromatography with Diode Arrays Detection (HPLC-DAD) and Mass Spectrometric Detection (HPLC-ESI-Q-ToF) were all applied to three small samples detached from the three painted (green-blue, white and red-yellow, respectively) areas of the flag. The combination of the data obtained with all these techniques made possible a comprehensive understanding of both the chemical composition and physical behaviour of the materials used by the artist and supported curators in defining the preventive conservation of this artwork. [ABSTRACT FROM AUTHOR]

The potential of principal component analysis (PCA), on combined first derivative near-infrared and Raman spectra, was explored and tested in order to exhaustively characterize different oil-paint models, prepared with linseed and poppy-seed oil, and to verify the behavior of these binders in the presence of a pigment. A series of oil-paint models, selecting pigments employed in artworks both in antiquity (like lead white, azurite, Afghanistan ultramarine) and contemporary art (such as phthalocyanine blue, zinc oxide and synthetic ultramarine blue), were prepared and analyzed by means of reflectance near-infrared and micro-Raman spectroscopic techniques. At first, PCA was applied by taking into account all oil-paint models, pigments and drying oils. Subsequently, new statistical models were built focusing only on single pigment subsets, hence offering a more realistic application of this method once the pigment had been identified. The proposed procedure allowed us to recognize the pigments and binding media used to prepare each model. In addition, it proved to be even sensitive to the drying oil employed in the oil-paint mixture, enabling its identification. The application of PCA to a combination of different spectral regions (6000–3900 cm − 1 along with 1900–260 cm − 1 ) allowed an enhanced level of spectral information to be extracted, with respect to its application on separated data sets. It represents also a powerful tool to differentiate oil-paint models on the basis of their composition, including oils and pigments. Moreover, we verified that after a natural ageing of 9 months, and in presence of a pigment, it is still possible to obtain information regarding the functional groups directly involved in the drying process (e.g., the 1st overtones of methylenic stretching, 5800 cm − 1 and 5698 cm − 1 , the C-H combination bands of methylenic stretching and bending modes, 4340 and 4261 cm − 1 , and the ν (C = C) stretching, 1654 cm − 1 ). [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive understanding of both the chemical composition and physical behaviour of modern materials is an important consideration in devising correct conservation treatments for contemporary artworks. To this end, national and international research projects and networks have been established that deal mainly with the preservation, conservation, and understanding of materials used by contemporary artists. This paper focuses on the self-taught artist Fernando Melani (1907–1985), one of the precursors of the Poor Art artistic movement in Italy, and for the first time provides a scientific viewpoint on the artist’s materials and works. The analyses, which mainly focus on the pigments/dyes found in his home-studio, were carried out primarily by using Fourier Transform Infrared Spectroscopy (FT-IR) and ultraviolet, visible, and near-infrared Fibre Optic Reflectance Spectroscopy (UV–Vis–NIR FORS). This paper emphasises the performance of FT-IR and FORS in the identification of contemporary artistic materials, since these two techniques have been found to produce highly complementary data. The use of both of these was required in order to obtain a comprehensive understanding of the composition of Melani’s materials. Furthermore, one of his artworks, named by Melani himself with its inventory number N. Inv. 2625 (1981), was investigated in situ with the sole use of the FORS technique. The results showed that Melani used traditional inorganic pigments as well as modern organic dyes. Calcite and barite were used as fillers and extenders. Sulphur and abrasive powder were also found, thus confirming his use of a large variety of non-conventional artists’ materials. [Copyright &y& Elsevier]