The Study of the Capodimonte Production: an Occasion for the Proposal of a Raman Database for Ancient Porcelains

In the past few years a comprehensive interdisciplinary study has been undertaken on some excavation fragments of 18 century porcelain from Capodimonte (Naples, Italy). The Capodimonte manufacture has had a very peculiar history; this makes it interesting per se to characterize its products, which can also be of use as a “case study” for a methodological objective. Analyses have been carried out on pastes, glazes and decorations in order to assess compositional and technological aspects of this production. Several analytical techniques were used, which included Raman macroand micro-spectroscopy and WD-XRF. We wanted in fact to test the suitability of Raman spectroscopy for a non-destructive and non-invasive analysis, possibly coupled with portable ED-XRF, in order to establish a significant “reference group” of Raman spectra for the Capodimonte production. The following step would be to enlarge this kind of study to other porcelain factories, in order to assess the possibility of an attribution of a porcelain object to a certain production on the basis of the Raman signatures of its paste and glaze. Several studies have in fact been published, demonstrating how the Raman spectra of a porcelain fragment or whole object can be obtained in a completely non-invasive way to determine body and glaze composition, making it possible to identify the type of porcelain, its manufacturing technology and often its provenance. There seems now to be a great need for the systematization of such a large corpus of spectroscopic data. Moreover, only a limited number of porcelain manufactures have been investigated so far; the study of other productions would be of great use for the establishment of a complete and reliable spectroscopic database on these materials. In order to assure as much as possible reliability, this will also require the standardization of the experimental procedure, for which some general criteria are presented. INTRODUCTION Historical Background In 1739 Charles of Bourbon, king of Naples, following the example of Royal Courts all over Europe, promoted the establishment of a porcelain manufacture, at first housed in the Royal Palace. After a few years devoted to the search for suitable raw materials and to experimentations of different recipes for the porcelain paste, in 1743 the porcelain manufacture officially started its work, and was relocated in the Royal woods of Capodimonte. During the following sixteen years, the factory produced high quality porcelain, often in the form of decorative objects, which served as gifts from the king to Italian and foreign noblemen, and were commercialized since 1745. The factory mark used all along the manufacture's activity was a fleur-de-lis painted in underglaze blue, or sometimes impressed under the bottom of the artefact, mostly in the case of figurines. It is clear from the rare historical sources that during the short life of the manufacture the quest for raw materials and the experimentations never ceased. In 1759, when he rose to the Spanish throne becoming Charles III of Spain, the king decided to move the porcelain production to Madrid, completely dismantling the Neapolitan factory. The Archaeometric Research Project The short-lived production of Capodimonte has not so far been the object of extensive archaeometric studies. Prof. Orazio Rebuffat was the first, in 1905, to provide chemical data regarding Capodimonte pastes and glazes. Only in 1995 more data were published regarding the chemistry, mineralogy, density and microstructure of some porcelain fragments found during excavations in the 1950s in the area formerly occupied by the manufacture. In the past 1 9th International Conference on NDT of Art, Jerusalem Israel, 25-30 May 2008 For more papers of this publication click: www.ndt.net/search/docs.php3?MainSource=65