Study of metallic components of historical organ pipes using synchrotron radiation X-ray microfluorescence imaging and grazing incidence X-ray diffraction.

A comparative study of the composition and microstructure of two different brass alloys from reed pipes, one from a Spanish baroque organ and the other from a modern one, was carried out. This study allowed us to determine the procedure followed to produce the brass used to make ancient reed pipes. Moreover the distribution and correlation of lead and other trace elements present into the main component of the brass, the copper and zinc phases, of the historical tongues and shallots were established. This chemical composition was compared with that of a tongue from a twentieth-century organ. The whole study was accomplished using a combination of laboratory and synchrotron radiation techniques. X-ray fluorescence was the technique used to obtain elemental and chemical imaging of the main phases and the trace elements at a sub-micrometer scale.

Advanced combined application of micro-X-ray diffraction/micro-X-ray fluorescence with conventional techniques for the identification of pictorial materials from Baroque Andalusia paintings.

The process of investigating paintings includes the identification of materials to solve technical and historical art questions, to aid in the deduction of the original appearance, and in the establishment of the chemical and physical conditions for adequate restoration and conservation. In particular, we have focused on the identification of several samples taken from six famous canvases painted by Pedro Atanasio Bocanegra, who created a very special collection depicting the life of San Ignacio, which is located in the church of San Justo y Pastor of Granada, Spain. The characterization of the inorganic and organic compounds of the textiles, preparation layers, and pictorial layers have been carried out using an XRD diffractometer, SEM observations, EDX spectrometry, FT-IR spectrometry (both in reflection and transmission mode), pyrolysis/gas chromatography/mass spectrometry and synchrotron-based micro-X-ray techniques. In this work, the advantages over conventional X-ray diffraction of using combined synchrotron-based micro-X-ray diffraction and micro-X-ray fluorescence in the identification of multi-layer paintings is demonstrated.

Non-destructive analysis of cultural heritage artefacts from Andalusia, Spain, by X-ray diffraction with Göbel mirrors.

The characterization of the phases present in artefacts has been normally carried out using XRD (Bragg-Brentano geometry) that requires sampling from artworks, being a destructive technique. However, X-ray diffraction with Göbel mirrors permits directly to study rough artefacts without sampling. Grazing incidence attachments can be used to characterize as much the superficial layer as the underlying ones in flat samples to obtain information about the depth profile of some samples. The combination of Göbel mirrors and measure at low fixed incidence angles allow to obtain information about the depth profile of bent samples. This work reports the alteration processes on the surface of the following cultural heritage artefacts: a rivet and a nail extracted from Pardon Gateway, located in the North façade of Mosque-Cathedral of Cordoba; a Roman arrow and a button from a Roman jacket obtained from an excavation in Baena (Cordoba); organ pipe from Cathedral of Zaragoza; lead seals from Seville City Hall collection. The main objective of this paper is the study through a totally non-destructive analytical method, X-ray diffraction with Göbel mirrors, of the superficial alteration of some metallic artefacts from cultural heritage. This knowledge allows us the election of appropriate methods to carry out the restoration of these artefacts.