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     

Microchemical investigation on Renaissance coins minted at Gubbio (Central Italy)

The bulk and surface chemical composition of Renaissance coins minted at Gubbio (Central Italy) from 1508 to 1516 and from 1521 to 1538 by Francesco Maria della Rovere is investigated by means of the combined use of different analytical techniques such as scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and optical microscopy (OM). The aim of the work is to determine the bulk chemical composition of these commonly used coins at Gubbio, to ascertain their surface nature and if they were coated by a thin film of silver or other white metals similar to silver.The results indicate that the coins were produced by coating a copper core with a thin film of silver and antimony, and also with lead whose thickness is of a few microns which is now scarcely present because the original silvered surface was almost entirely removed by degradation phenomena. Furthermore, the SEM+EDS results show that the surface content of silver and antimony cannot be attributed to long-term selective corrosion phenomena leaving the coin slightly silver or antimony enriched. Therefore, the presence of silver or apparently silver-like metals i.e. antimony and lead, could be considered as a deliberate surface finishing of the coins obtained via inverse segregation or intentional selective corrosion based on pickling solutions or a combination of them. From a historical point of view the presence of a Ag or Sb film on the surface of the coins discloses the occurrence of a period of economic difficulties. PACS 68.55.Jk; 68.35.Dv; 68.37.Hk; 68.55.Nq; 81.05.Bx     

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     

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     

Characterization of blue decorated Renaissance pottery fragments from Caltagirone (Sicily,Italy)

Renaissance blue decorated pottery fragments from the archaeological site of Caltagirone (Sicily, Italy) were analysed by scanning electron microscopy – energy dispersive X-ray spectrometry (SEM/EDS). The samples were dated back to 16th century AD on the basis of archaeological observations. The micro-chemical analyses were performed on the ceramic body and the surface decorated layer of the samples. Particularly, the investigation was addressed the characterization of the coating blue decorations. The obtained results allowed us to clearly identify smalt as pigment. Also the presence of arsenic (As) was revealed and the Co/As ratio values were calculated and related to the different process used for the pigment preparation. Further spectroscopic analyses, performed through X-ray absorbance spectroscopy (XAS), carried out at the Co K-edge, confirmed the micro-analytical results and permitted us to identify the oxidation form and the local environment of cobalt atoms. PACS  81.05.Mh; 82.80.-d; 68.37.Hk     

Characterisation and reproduction of yellow pigments used in central Italy for decorating ceramics during Renaissance

This study presents the characterisation of prototypical yellow pigments used during the Renaissance period in Italy and the successful reproduction of homologous materials in accordance with the ancient recipes. Moreover, a large number of yellow decorative layers of Sicilian ceramic artefacts dated back from 13th to the 19th century have been selected and the main chemical, structural and minero-petrografic features have been studied by X-ray diffraction, optical microscopy and scanning electron microscopy-energy dispersive spectrometry. These results have been compared with literature data of some yellow decorations of Renaissance ceramics made in central Italy. Comparison has also been made with homologous materials that have been successfully reproduced in accordance with ancient recipes described by Cipriano Piccolpasso in the textbook: “I Tre Libri dell’Arte del Vasaio” using the same ingredients proposed by this artist. Such yellow materials reproduce the typical yellow colorants used by craftsmen of relevant sites for ceramic fabrication in central Italy, namely Città di Castello, Urbino and Castel Durante, during the 16th century.Comparative arguments have shown some intriguing differences that are indicators of both technological transfer processes between central and southern Italy as well as of some local implementations likely due to specific raw materials locally available. PACS 81.05.Je; 82.80.-d; 68.37.Hk; 68.55.-a; 61.66.Fn; 61.10.Nz     

The precipitation in Italy during the period Autumn 1988–Spring 1990

Summary In Italy the period November 1988–April 1990 shows an anomalous trend of precipitations. Severe drought during the cold season and above normal amounts during summer, in particular in July 1989, was recorded. In this paper an analysis is carried out of this anomaly which explains the phenomenon on the basis of the meteorological patterns, recorded during the two years, and excludes that it could be significant of an eventual climatic change.     

Investigation of gold nanotubes of chiralities (4, 3) and (5, 3) in the Hubbard model

The quantum systems of gold nanotubes of chiralities (4, 3) and (5, 3) have been studied in the framework of the Hubbard model for arbitrary values of the Coulomb interaction and electron concentration. The anticommutator Green’s functions of nanosystems, the energy spectra, and the ground state, ionization, and electron affinity energies have been calculated. The obtained data have been used for comparative analysis of nanosystems.     

Atomic steps on the Si(111) surface during submonolayer gold adsorption

The effect of adsorption of submonolayer gold coatings on the Si(111) surface morphology in the temperature range 850–1260°C has been investigated by means in situ ultrahigh-vacuum reflection electron microscopy and ex situ atomic force microscopy. Reversible transformations of the silicon surface: from regular monoatomic steps to step bunches, depending on the gold coverage and direction of the electric current resistively heating the crystal, have been revealed. Stability of the regular distribution of monoatomic steps upon heating of the crystal by an alternating current is shown. The effect of an electric field applied to the sample on the diffusion of silicon and gold adatoms has been analyzed taking into account the effective adatom charge.     

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     

Determination of gold leaf thickness in a Renaissance illumination using a nondestructive approach

In this work, the thickness of the gold leaf applied in the Manueline foral charter of Murça (illuminated in 1512) will be determined using X‐ray fluorescence. In the frontispiece of the Manueline foral charter of Murça, the capital D was gilded using a gold leaf over a priming made of lead white. The characteristic lines of Pb (namely Lα and Lβ), although attenuated in the Au layer, are still visible in the X‐ray fluorescence spectra. By determining the intensity ratio Lα/Lβ and comparing it with the ratio for an infinitely thick sample, the thickness of the attenuating material can be determined. Using this methodology, the thickness of the gold leaf applied in the charter of Murça was estimated as 1.6 µm. Copyright © 2013 John Wiley & Sons, Ltd.     

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     

Production and loss of N2 + ions during the decay period of plasmas produced in helium-nitrogen mixtures

The time dependence of the number density of N₂ ⁺ ions during the decay period of plasmas produced in helium containing 0.05, 0.17 and 0.5 percent nitrogen was studied in the pressure range from about 0.3 to 7 Torr by means of mass spectrometer techniques. During the early part of the afterglow period the time dependence of N₂ ⁺ is controlled by ambipolar diffusion loss towards the plasma container walls. The product of the ambipolar diffusion coefficientD _a and the reduced pressurep ₀ wasD _ap₀=900± 50 cm² Torr/sec. The production of N₂ ⁺ by collisions between metastable nitrogen molecules determines the temporal behavior of the N₂ ⁺ density during the late afterglow for extremely pure discharge conditions. From the data it follows that the metastable molecules involved are de-excited by collisions with ground state helium atoms with a rate constant of 3.4 × 10^?15 cm³ sec^?1, while the radiative lifetime of these metastable molecules is at least 20 msec. The surface catalytic efficiency for de-excitation upon striking the molybdenum covered plasma container walls was estimated to be smaller than 10^?3. Energy and radiative lifetime requirements suggest that N₂ ⁺ is produced during the plasma decay period by the process N₂ (a′¹ Σ _u ^? )+N₂ (a′¹σ _u ^? →N₂ ⁺ (X²Σ _u ⁺ )+N₂(X)+e.     

Production and loss of N 2 + , Ne+ and Ne 2 + during the decay period of plasmas produced in neon-nitrogen mixtures

Studies of the time dependencies of the number density of N ₂ ⁺ , Ne⁺ and Ne ₂ ⁺ ions have been made during the decay period of plasmas produced in neon containing various concentrations of nitrogen molecules. Reaction rate constants were obtained for N ₂ ⁺ +N₂+Ne→N ₄ ⁺ +Ne((1.2±0.2)×10^?29 cm⁶ sec^?1) and Ne⁺+N₂→N ₂ ⁺ + Ne ((2.9±0.3) × 10^?12 cm³ sec^?1). The ambipolar diffusion coefficient of N ₂ ⁺ in neon was found to beD _a p _o =350±20 cm² sec^?1 Torr.     

An alternative model of the reconstructed (100) surfaces of gold,platinum and iridium

Gold, platinum and iridium (100) clean surfaces are reconstructed, the widely accepted model of the reconstruction is that the top layer is a slightly compressed hexagonal (111) plane. The aim of this paper is to show that there is an alternative model to explain the reconstruction that requires very little displacement of the surface atoms. No proof can be given of either model, but both of them should be used in LEED intensity calculations.     

The effect of gamma de-excitation competition on the (α, n) and (α, 2n) reactions on gold and antimony

Absolute cross sections for P¹⁹⁷Au(α, n)²⁰⁰Tl ¹⁹⁷Au(α, 2n)¹⁹⁹Tl, ¹²¹Sb(α, n)¹²⁴I and ¹²¹Sb(α, 2n)¹²³I are measured in the energy range from threshold to 27 Me V.The experimental results are interpreted in terms of evaporation statistical theory, including gamma de-excitation. The values of the level density parameters and of the average γ-ray strength for the compound systems are extracted.     

Electromigration of gold (high concentration) in lead

The steady state method was used to study the electromigration of ¹⁹⁵Au in lead doped with 680 ppm Au. In the temperature range 165–270°C Au migrates toward the anode, as in the case of more dilute solutions; but the effective charge increases in magnitude with decreasing temperature at a faster rate than that observed for dilute Pb(Au) samples, so that the difference between the effective charge for the 680 ppm samples and that for dilute samples becomes larger as the solubility limit is approached. A simple model, which allows for formation of Au doublets in equilibrium with the singlets, predicts an apparent increase of Z¹ with concentration of impurity at lower temperatures somewhat greater than the observed effect.     

Radioactivity in waters of Mt. Etna (Italy)

Radioactivity in underground waters from Mt. Etna was investigated on the basis of 13 samples. The samples were collected from springs, wells and galleries around the volcano. Water from nine out of thirteen intakes is used for consumption. Activity concentration of uranium isotopes ^234,238U, radium isotopes ^226,228Ra and radon ²²²Rn were determined with the use different nuclear spectrometry techniques. The measurements of radium and radon activity concentration were performed with the use of a liquid scintillation counter. The determination of uranium isotopes was carried out with the use of alpha spectrometry. All samples show uranium concentration above Minimum Detectable Activity (MDA), with the highest total uranium (²³⁴U + ²³⁸U) activity concentration equal to 130 mBq/l. For radium isotopes, all samples except one showed the activity concentration below MDA. Radon activity concentration was within the range from 1 to 13 Bq/l, hence these waters can be classified as low-radon waters.