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The article focuses on the conservation of two stained-glass windows in the basilica of Santa Croce attributed to the anonymous Master of Figline and dated 1320-1330. The windows are among the oldest and most impressive stained glass works in Florence. A unique, interdisciplinary approach is offered by presenting technical results and restoration methodologies from the stained glass' conservation, and data from analyses of the windows' glass (conducted both in situ and in the laboratory), together with observations from the restoration of the Master of Figline's monumental wooden crucifix in the high chapel of Santa Croce, and a re-consideration of the anonymous artist from an art historical perspective in light of new data. The study yields discoveries about chemical composition, glass manufacture, and fourteenth-century stained-glass practice.

Fluorescence LIDAR imaging has been already proposed in several studies as a valuable technique for the remote diagnostics and documentation of the monumental surfaces, with main applications referring to the detection and classification of biodeteriogens, the characterization of lithotypes, the detection and characterization protective coatings and also of some types of pigments. However, the conservation and documentation of the cultural heritage is an application field where a highly multi-disciplinary, integrated approach is typically required. In this respect, the fluorescence LIDAR technique can be particularly useful to provide an overall assessment of the whole investigated surface, which can be profitably used to identify those specific areas in which further analytical measurements or sampling for laboratory analysis are needed. This paper presents some representative examples of the research carried out in the frame of the PRIMARTE project, with particular reference to the LIDAR data and their significance in conjunction with the other applied techniques. One of the major objectives of the project, actually, was the development of an integrated methodology for the combined use of data by using diverse techniques: from fluorescence LIDAR remote sensing to UV fluorescence and IR imaging, from IR thermography, georadar, 3D electric tomography to microwave reflectometry, from analytical techniques (FORS, FTIR, GC-MS) to high resolution photo-documentation and historical archive studies. This method was applied to a 'pilot site', a chapel dating back to the fourteenth century, situated at 'Le Campora' site in the vicinity of Florence. All data have been integrated in a multi-medial tool for archiving, management, exploitation and dissemination purposes.

One of the characteristics of the Books of ours produced in Europe in the 15th century is the richness of the materials used in the decoration of the devotional images, representing the social and economic power of its owner and transforming them into luxury objects. This was one reason why these books became "best-sellers", carefully donated from generation to generation. The core point of this article is the presentation of the ethical approach for the conservation of a French Book of Hours dating from the early 15th century, now stored in the Library of the 18th century Mafra National Palace (Lisbon, Portugal), based on the study and comprehension of the techniques and materials used. In fact, for the full appreciation and understanding of the work involved in the construction of the Book of ours and the development of a conservation strategy, it is crucial to know which materials were used, determine their conservation status, and attest the interventions suffered throughout its existence. An interdisciplinary team studied the historic context of this prayer book, its techniques and material composition, its conservation condition, and decided the curative conservation approach (Araújo, 2012). In this article we intend to describe all the steps taken and explain the decision making, taking into account conservation ethics.

This work presents a methodological approach to the study of ancient wooden artefacts by using FT-IR techniques. Sampling is one of the most important steps in investigating works of art. However, samples should be taken only when this operation does not appreciably modify any of the parts, or change the integrity, of the wooden artefacts in question. Although it was invasive, a low-destructive method of sampling was used on wood meal in order to obtain reproducible results. Moreover, two modes of operation were compared, namely the transmission mode (carried out on pellets of wood meal mixed with KBr) and the Attenuated Total Reflectance (ATR) mode (carried out directly on wood meal). For the former, the effect of the concentration of wood in KBr also was considered. The results evidenced a similar quality of spectra, although a different sensitivity between the two techniques in some spectral ranges was observed. The final focus of this research will be on validating the use of IR spectra to date wooden materials.

An understanding of the composition of natural and synthetic dyes used in ancient textiles and rugs is important for conservation purposes and to determine the origin of a textile or rug. colorants or dyes are traditionally analysed by means of separation methods and ultraviolet­visible spectroscopic techniques that require sampling. this contribution focuses on establishing a fast, non-invasive, and in situ measurement procedure based on ultraviolet­visible­near infrared reflectance spectroscopic techniques for the characterization of dyes in ancient textiles or rugs manufactured in the Mediterranean basin and Middle East. For this purpose a collection of specimens on wool supports was prepared following ancient dyeing recipes. the samples were subsequently measured in the 230­2500 and 350­1700 nm ranges to create a spectroscopic database that was then compared with spectra acquired from textiles and rugs in order to characterize the dyes present.

We report the neutron vibrational spectra of indigo and its model compounds thioindigo and isatin. The neutron data extend the low energy range of the vibrational spectra of these molecules. The assignments, made with the help of ab-initio calculations, give convincing fits between the observed and scaled calculated results, and correct errors in the published literature. The indigo eigenvectors are described in terms of those of its model compound isatin. Finally, candidate modes, that could be used to study indigoids in matices (e.g. 'Maya Blue'), are selected.

A hyperspectral scanner operating in the visible (VIS) to near infrared (NIR) range (400-1000 nm) and based on a prism-grating-prism line-spectrograph connected to a silicon CCD camera is presented. The characteristics of this scanner are 0.1 mm spatial sampling over a 1 × 1 m2 surface and approximately 1 nm spectral sampling in the wavelength range 400-900 nm. The results provide useful information, in particular or the characterisation of pigments and dyes. Furthermore, the acquired images can also be used for colorimetric applications. In addition, application of a principal components analysis (PCA) algorithm to the spectral data, with the pixels as objects and the wavelengths as variables, has made it possible to show areas painted with different materials as statistically uncorrelated images. Results obtained using this hyperspectral scanner on different polychrome surfaces will be discussed.

UV-Vis Reflectance Spectroscopy and Raman Microspectroscopy provide a rapid way to unequivocally identify the pre-Columbian pigment Maya blue. Spectra of modern synthetic materials are compared with data from a contextualized archaeological sample and from an object in the collection of the Los Angeles County Museum of Art. UV-visible spectroscopy and Raman Microspectroscopy, together with complementary techniques such as Fourier Transform Infrared Microspectroscopy (FTIR) reveal significant differences between spectra of indigo as pure crystalline solid or as complexed by palygorskite. These techniques are thus extremely specific, being able to identify Maya blue as a prepared pigment, rather than just detecting its ingredients, indigo and palygorskite. Fiber optics UV-Vis Reflectance Spectroscopy (FORS) and Raman Microspectroscopy (RM) present the additional advantage of being completely non-invasive, and therefore extremely amenable to the study of works of art. Lightweight portable FORS devices make it possible to perform measurements in situ on wall paintings and other immovable objects. The spectral differences between pure indigo and the indigo-palygorskite complex can be interpreted in terms of different hydrogen bonding configurations for the indigo molecule

To date, the study of fluorescence images of polychrome surfaces has not proceeded beyond more than a stage that supplies visual information. The recent availability of spectral imaging systems for providing multi-pixel spectral information has led to the development of non-destructive methodologies suitable for readily acquiring and analysing both reflectance and fluorescence spectral images. The spectral information obtained from a specific area is stored as a cube, which is defined by the two spatial dimensions of the surface (x and y), and by the spectrum of the reflected or emitted light as the third dimension. In the present communication, a Fourier Transform Interferometric Imaging System (FTIIS) was applied to the study and characterization of the reflectance and fluorescence spectra of several pigments and dyes. In addition, a comparison between the fluorescence images acquired with the FTIIS and the traditional fluorescence photographs has been provided.

The painting Il ritratto della figliastra (Portrait of the Stepdaughter) by Giovanni Fattori (1889, Gallery of Modern Art, Pitti Palace, Florence) was investigated using non-invasive fibre optics reflectance spectroscopy (FORS). The use of compact and transportable instrumentation made it possible to easily record spectra of the polychrome surface at the restorer’s atelier during the restoration work. The results of colour analysis before and after the cleaning procedure of the painting are reported and discussed, together with an attempt at pigment identification.