A scientific approach to the attribution problem of renaissance ceramic productions based on chemical and mineralogical markers

Renaissance lustred majolica shards from Gubbio and Deruta (Central Italy) were investigated in order to point out differences in chemical and mineralogical composition between these two very similar Italian potteries and furthermore to find correlations with the local raw clay materials probably used for their production. Chemical and mineralogical analysis on the ceramic body were performed by ICP-OES (inductively coupled plasma optical emission spectroscopy) and XRD (X-ray diffraction), respectively. Investigation of the ceramic body revealed significant differences on calcium content indicating that it could be used as a marker for the two different productions.     

Italian Renaissance and Hispano-Moresque lustre-decorated majolicas: imitation cases of Hispano-Moresque style in central Italy

An investigation was carried out on Renaissance lustre-decorated majolica shards, found during excavations made in Umbria (central Italy) and defined by experts, on the ground of the surface decoration, as imitations of the Hispano-Moresque style. A comparison between this particular kind of samples, produced in central Italy, and some Hispano-Moresque lustre shards has been performed. The ceramic bodies as well as the lustred surfaces have been analysed by means of several techniques: inductively coupled plasma optical emission spectrometry, X-ray diffraction (XRD), atomic absorption spectrometry with electrothermal atomisation and scanning electron microscopy. By means of XRD analysis the presence of cosalite (Pb₂Bi₂S₅) has been disclosed in the Italian lustre decorations but was not observed in the Hispano-Moresque ones. A hypothesis has been made, considering bismuth as a discriminating element, between lustres produced in central Italy and the Hispano-Moresque ones. We thought that the Italian artisans were able to manage the use of bismuth. Therefore a recipe, quite similar to the one employed by the Spanish artisans, was used by the Italian ceramists if their aim was to imitate the Hispano-Moresque style. Received: 4 November 2002 / Accepted: 6 November 2002 / Published online: 28 March 2003 RID="*" ID="*"Corresponding author. Fax: +39-06/9067-2316, E-mail: pad@mlib.cnr.it     

A new light on a first example of lustred majolica in Italy

A study has been realised to elucidate the first step of lustre production in Italy. With this aim in mind, an investigation was carried out on an emblematic lustred object: Baglioni’s albarello. It is conserved at Louvre museum and it is considered as one of the very first examples of lustred object produced in Italy. The characteristics of the lustred film have been determined, identifying interesting aspects that may be used to scientifically confirm the origin of this object. This study was completed by the investigation of other objects: a not lustred albarello, still decorated with the coat of arms of Baglioni’s family and a lustred plate with the coat of arms of the Montefeltro family. The two Baglioni’s albarelli are stylistically and historically considered as produced in one of the numerous workshops of Deruta. The origin of the Montefeltro’s plate, although from central Italy, is not precisely attested. In order to acquire more information, clarifying the origin and place of production of these objects, a comparison of their physico-chemical characteristics with results obtained and already published on different well-attested productions, such as Islamic, Hispano-Moresque and Italian, was carried out. For what concerns the museum objects, the use of non-destructive investigation techniques was mandatory. For this reason, ion beam techniques as PIXE and RBS have been used at AGLAE facility, as well as a new X-ray micro-diffraction equipment, at C2RMF. Moreover, the results were compared with data obtained on shards of certain production origin, by means of chemometric techniques. Some hypothesis concerning the place of production of the examined objects have been formulated.     

Photoluminescence emissions of ceramics: a marker of production technology

Photoluminescence (PL) measurements have been performed on different sets of ceramic shards; the results obtained from the ceramic bodies of lustred majolicas produced in Iraq, Italy and Spain are reported. Non-lustred samples are analysed for comparison. The spectra obtained from all the lustred samples show PL emission bands that are attributed to the presence of α-quartz and diopside. The photoluminescence of the lustre-decorated ceramics is possibly a fingerprint of the particular production technology of lustre. PACS 81.05.Mh; 78.55.Hx     

Luminescence properties of lustre decorated majolica

Luminescence measurements have been performed on several Italian Renaissance ceramic shards produced in central Italy, as well as on some others from Hispano–Moresque and Fatimid periods. The aim of this study was the characterisation of the raw materials used to manufacture lustre decorated majolica. At first, the thermoluminescence (TL) dating of all ceramic bodies was performed, because the shards lacked sure chronological attribution, having been provided by private collectors, or found during emergency restoration works or archaeological surveys. To characterise the defects and the recombination centers of the different components of the ceramics (ceramic body, glaze, glaze, and lustre), radioluminescence (RL) measurements have been performed on samples representative of each historical period. The dating results are reported, as well as the preliminary RL results. PACS 78.66Jg; 87.66Sq; 81.05.Mh     

Production of gold and ruby-red lustres in Gubbio (Umbria,Italy) during the Renaissance period

The aim of this work is to gain a further insight into the knowledge of the production process of lustre-decorated ancient majolicas. Lustre is a sophisticated technique employed in the decoration of majolicas as used in central Italy during the Renaissance period. It consists of a beautiful iridescent gold or ruby-red thin metallic film, containing silver, copper and other substances and obtained in a reducing atmosphere on a previously glazed ceramic. Nowadays, it is not possible to replicate the outstanding results obtained by the ancient ceramicists, since the original recipes were lost. It is quite interesting to study lustre-production technology by means of analytical techniques now employed for advanced research on materials (XRD, ETAAS, ICP-OES, TEM-EDX-SAED and UV-Vis). In this work, we have focussed our attention on ceramic fragments decorated with both gold and ruby-red lustres, which were difficult to obtain due to complex reduction conditions required and which were a prerogative of Gubbio production. The two lustre colours differ in their chemical composition as well in their nanostructure. The presence of bismuth was disclosed and it was ascertained to be a distinctive feature of the Italian production. PACS 78.67.Bf; 81.05.Je; 68.37.Lp; 68.37.Hk; 68.90.+g     

Characterisation of decorations on Iranian (10th–13th century) lustreware

It has been recently shown that lustre decoration of Medieval and Renaissance pottery consists of silver and copper nanoparticles, dispersed within the glassy matrix of the ceramic glaze. Lustre surfaces show peculiar optical effects, such as metallic reflection and iridescence. Here we report the findings of a study on lustred glazes of several shards belonging to Iranian pottery of the 10th and 13th centuries, decorated on both sides. Two different glazes, depending on the side of the sample, have been identified. Different lustre chromatic effects are characterised by the relative presence of silver- and copper-metal nanoparticles dispersed in the glassy matrix. PACS 61.46.+w     

Heterogeneous distribution of metal nanocrystals in glazes of historical pottery

It has been recently shown that lustre decoration of medieval and renaissance pottery consists of silver and copper nanocrystals, dispersed within the glassy matrix of the ceramic glaze. Lustre surfaces show peculiar optical effects such as metallic reflection and iridescence. In many cases, lustre appears overlapped to colored drawings. Here we report the findings of a study on glazes, pigments and lustre of several shards belonging to Deruta and Gubbio pottery of XVI century. The components of glazes and pigments have been identified. Lustre is confirmed to be characterised by silver and copper metal nanocrystals inhomogeneously dispersed in the glassy matrix of the glaze. In the case of lustre overlapped to colored decorations, we found two contradictory cases. The first consists of a lustre surface successfully applied over a blue smalt geometrical drawing. The second consists of a lustre surface, unsuccessfully applied over a yellow lead-antimonate pigment. The yellow pigment hinders the formation of lustre and removes crystals of tin dioxide, normally present in the glaze as opacifier.     

XAFS study of copper and silver nanoparticles in glazes of medieval middle-east lustreware (10th–13th century)

It has recently been shown that lustre decoration of medieval and Renaissance pottery consists of silver and copper nanoparticles dispersed in the glassy matrix of the ceramic glaze. Here the findings of an X-ray absorption fine structure (XAFS) study on lustred glazes of shards belonging to 10th and 13rd century pottery from the National Museum of Iran are reported. Absorption spectra in the visible range have been also measured in order to investigate the relations between colour and glaze composition. Gold colour is mainly due to Ag nanoparticles, though Ag⁺, Cu⁺ and Cu²⁺ ions can be also dispersed within the glassy matrix, with different ratios. Red colour is mainly due to Cu nanoparticles, although some Ag nanoparticles, Ag⁺ and Cu⁺ ions can be present. The achievement of metallic Cu and the absence of Cu²⁺ indicate a higher reduction of copper in red lustre. These findings are in substantial agreement with previous results on Italian Renaissance pottery. In spite of the large heterogeneity of cases, the presence of copper and silver ions in the glaze confirms that lustre formation is mediated by a copper- and silver-alkali ion exchange, followed by nucleation and growth of metal nanoparticles.     

The use of small angle X-ray scattering (SAXS) for the characterisation of lustre surfaces in Renaissance majolica

In this work some Renaissance lustre decorated ceramics have been examined. Our attention was directed to lustre which is a thin decorative metallic film applied on the surfaces of previously glazed ancient pottery.Some 16th century lustre ceramics shards from Deruta, Umbria (Italy) have been analysed by small angle X-ray scattering (SAXS) in order to characterise the dimension of the metal nanocrystals forming the thin lustre layer. This technique appeared to be a powerful tool to characterise lustre films nanostructure and may be successfully used for this purpose together with transmission electron microscopy (TEM). Furthermore, SAXS measurements are extremely suitable for the determination of polydispersity and average interparticle distance.The lustre surfaces have been also analysed by scanning electron microscopy plus X-ray energy dispersive spectrometry (SEM–EDX) in order to identify the metals present (silver, copper or both of them) and to establish copper/silver ratios. From the comparison between SAXS results and compositional data, it was possible to conclude that copper particles are smaller than the silver ones. We have evidenced how the microtexture as well as the chemical composition of the lustre layers are responsible for the gold or red colour typical of the lustre films.     

First-time observation of Mastro Giorgio masterpieces by means of non-destructive techniques

For the first time some excellent pieces belonging to the majolica production of the great master Giorgio Andreoli from Gubbio (Central Italy) have been characterized from a chemical and structural point of view with the aim to identify the composition of both pigments and lustres. A series of particle-induced X-ray emission (PIXE), Rutherford backscattering spectrometry (RBS) and Raman analyses have been performed on some plates coming from Museo del Palazzo dei Consoli (Gubbio) and several French museums (Louvre, Musée National de la Céramique, Musée National de la Renaissance) lustred by Giorgio Andreoli and decorated by famous majolica painters such as Francesco Xanto Avelli. The three techniques are complementary and useful in the investigation of art objects since they are non-destructive. Furthermore, the low detection limits allow the identification of all elements and compounds present, and RBS allows concentration profiling, too. It is worth noticing that the examined objects are characterized by the presence of both gold and ruby-red lustres, a peculiarity of Mastro Giorgio’s technique. The measurements by PIXE and RBS have been carried out on the AGLAE accelerator at C2RMF, Louvre Palace. PACS 78.67.Bf; 81.05.Je; 68.37.Lp; 68.37.Hk; 68.90.+g     

Bismuth knowledge during the Renaissance strengthened by its use in Italian lustres production

The knowledge of bismuth during the XV and XVI centuries represents an open question since, according to some authors, this element was confused with lead, tin and silver. On the contrary, G. Agricola (1494–1555), the pioneer of mineralogical science in Europe, in his two works (De Natura Fossilium, Lib X, 1546 and Bermannus Sive De Re Metallica Dialogus, 1528) asserts that bismuth was considered as an element distinct from the other metals at that time. This question gave rise to some interest, and von Lippmann in 1930 wrote a treatise dealing with the history of bismuth between 1400 and 1800. In this work we present the results obtained on Italian and Hispano–Moresque shards studied by means of X-ray diffraction, atomic absorption spectrometry with electrothermal atomisation, inductively coupled plasma optical emission spectrometry and scanning electron microscopy. It seems that our work could provide a new and important contribution to this debate, because we found bismuth in lustre composition of Renaissance shards produced in central Italy. Furthermore, we found that it could also be considered as a discriminating element between Italian and Hispano–Moresque productions, useful to assess their origin. PACS 81.05.Je; 82.80.-d; 61.10.Nz     

Glancing-incidence X-ray diffraction of Ag nanoparticles in gold lustre decoration of Italian Renaissance pottery

Lustre is known as one of the most significant decorative techniques of Medieval and Renaissance pottery in the Mediterranean basin, characterized by brilliant gold and red metallic reflections and iridescence effects. Previous studies by various techniques (SEM-EDS and TEM, UV-VIS, XRF, RBS and EXAFS) demonstrated that lustre consists of a heterogeneous metal-glass composite film, formed by Cu and Ag nanoparticles dispersed within the outer layer of a tin-opacified lead glaze. In the present work the investigation of an original gold lustre sample from Deruta has been carried out by means of glancing-incidence X-ray diffraction techniques (GIXRD). The study was aimed at providing information on structure and depth distribution of Ag nanoparticles. Exploiting the capability of controlling X-ray penetration in the glaze by changing the incidence angle, we used GIXRD measurements to estimate non-destructively thickness and depth of silver particles present in the first layers of the glaze. PACS 61.10.Nz; 61.10.Eq; 81.70.-q; 61.46.+w     

How the masters in Umbria,Italy, generated and used nanoparticles in art fabrication during the Renaissance period

Lustre was one of the most sophisticated techniques for the decoration of majolicas during the Renaissance period. Lustre consists of a thin metallic film containing silver, copper and other substances like iron oxide and cinnabar applied in a reducing atmosphere on a previously glazed ceramic. In this way, beautiful iridescent reflections of different colours (in particular gold and ruby-red) are obtained. The characterisation and the study of lustre-decorated majolicas is of great interest for archaeologists, but also offers possibilities for producing pottery with outstanding decoration today, following ancient examples, since nowadays Italian artisans are interested in the reproduction of the ancient recipes and procedures. Moreover, it can even suggest new procedures for obtaining uniform thin metallic films for technological applications. A study has been carried out on ancient lustre layers using numerous different analytical techniques such as XRD, SEM–EDX, TEM–EDX–SAED, ETAAS, ICP–OES, UV–vis reflectance spectroscopy and SAXS. Lustre films were shown to be formed by copper and silver clusters of nanometric dimension. The colour and the properties of the lustre films depend on the elemental composition of the impasto applied to the ceramic surface as well as on other factors like the metallic nanocluster dimension, the firing conditions, the underlying glaze composition and the procedure used. Received: 12 August 2002 / Accepted: 14 August 2002 / Published online: 8 January 2003 RID="*" ID="*"Corresponding author. Fax: +39-6/9067-2445, E-mail: pad@mlib.cnr.it     

Technological study of ancient ceramics produced in Casteldurante (central Italy) during the Renaissance

In order to recover the ancient tradition concerning the materials used for the decoration, majolica shards produced during the Renaissance period in Casteldurante, a famous centre for ceramic production in Italy (Marche), have been examined. In the present study, pigments used for the decorations have been investigated by means of inductively coupled plasma optical emission spectrometry (ICP-OES), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM-EDX) and diffuse-reflectance UV-Vis spectroscopy. Ochre, lead antimonate yellow, copper-based pigment and smalt have been used as colourants to obtain respectively yellow-orange, yellow, green and blue decorations in accordance with what is reported by the ancient recipes. PACS 81.05.Mh; 82.80.-d; 61.66.Fn; 61.66.Hq     

Classification of ancient Etruscan ceramics using statistical multivariate analysis of data

About one hundred Etruscan ceramic shards dating from the VIII to the IV century BC and coming from the archaeological excavation at Pian di Civita in Tarquinia (central Italy) have been analyzed by inductively coupled plasma optical emission spectrometry and flame atomic emission spectrometry in order to settle their provenance and to acquire knowledge about the ceramic production technology. The examined shards belong to the class of the depurata pottery, a fine ware produced in Tarquinia over a long period, and are representative of different sub-classes. The samples have been analyzed for fifteen elements (Ca, Al, Mg, Fe, Ti, Cr, Cu, Ni, Zn, Mn, Zr, Sr, Na, K and Rb). The data acquired have been treated by multivariate analysis techniques such as principal component analysis and Kohonen artificial neural networks. Most of the analyzed shards have been locally produced as belonging to a unique large group. A continuity in usage of both choice of materials and technology has been recognized. PACS 02.50.Sk; 81.05.Mh; 82.80.-d     

Microstructural and thermal characterization of neolithic ceramics

The aim of this research was to characterize some Neolithic ceramic finds collected during an excavation carried out at Lugo di Grezzana (Verona, Italy). Pottery shards with different paste and tempers were analyzed to better understand the manufacturing and firing technologies used for their production. Another task of the study was to determine whether highly refined artefacts, found in the site and resembling figulina-type ceramics, were of local production or imported from other places in the north of Italy, where the production of this sort of product has already been unambiguously assessed. Several results emerged from this investigation, providing indications on the finds from this Neolithic settlement and, therefore, on the technological expertise achieved by the primitive community. Moreover, a comparative study carried out on refined ceramic products found in Lugo and genuine figulina items from other northern Italian sites suggests that no trading exchange and commercial routes existed among those primitive communities.     

Non-destructive identification of green and yellow pigments: the case of some Sicilian Renaissance glazed pottery

Selected decorated Renaissance ceramic fragments, found during the excavation of a Sicilian archaeological site (Caltagirone, Sicily, South Italy), have been studied by combining scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and X-ray absorbance spectroscopy (XAS). The study was aimed at providing microchemical and microstructural characterization of the colored glazed coatings in order to elucidate the nature of the pigments in the decorative layers, and in the glaze itself. From the obtained results, the general perspective has been the identification of information to be used for a reliable recognition of the production techniques.     

Silver and copper nanoclusters in the lustre decoration of Italian Renaissance pottery: an EXAFS study

Lustre is one of the most important decorative techniques of the Medieval and Renaissance pottery of the Mediterranean basin, capable of producing brilliant metallic reflections and iridescence. Following the recent finding that the colour of lustre decorations is mainly determined by copper and silver nanoclusters dispersed in the glaze layer, the local environment of copper and silver atoms has been studied by extended X-ray absorption fine structure (EXAFS) spectroscopy on original samples of gold and red lustre. It has been found that, in gold lustre, whose colour is attributed mainly to the silver nanocluster dispersion, silver is only partially present in the metallic form and copper is almost completely oxidised. In the red lustre, whose colour is attributed mainly to the copper nanocluster dispersion, only a fraction of copper is present in the metallic form. EXAFS measurements on red lustre, carried out in the total electron yield mode to probe only the first 150 nm of the glaze layer, indicated that in some cases lustre nanoclusters may be confined in a very thin layer close to the surface. PACS 61.46.+w; 81.05.Kf; 61.10.Ht