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Ahmed Elsayed
Investigations methods to study corrosion of some ancient Islamic copper coins at Faculty of arts museum, Sohag university, Egypt

Through the time, copper affected by deterioration factors that interact with environment. Oxygen causes corrosion of copper artifacts and forms copper oxides, meanwhile it starts to mineralize and backs to its natural structure. This research studied five Islamic copper coins at faculty of arts museum in Sohag University by Examination and Analytical methods to identify the corrosion nature and its effects on the coins. The Experimental Techniques were used, such as Stereo microscope, X-Ray Radiography, SEMEDX, and XRD. Results show that coins have more cracks and different corrosion layers. The chemical study (EDXXRD) shows that the main element in coins is copper with some other elements such as sulfur, chloride, calcium, magnesium, aluminum, and silicon which can be found in Egyptian soil composition or as blemish in metals compound. The main compounds were copper oxides, Cuprite (Cu2O), and Tenorite (CuO). Copper chlorides as Atacamite, Paratacamite (Cu2(OH)3Cl) as result of Chloride Ions.

Mauro Lo Brutto, Maria Grazia Spera
3D mosaics survey: analysis of photogrammetric/computer vision approach in a metrological context

The goal of the paper is evaluate photogrammetric/computer vision approach in a metrological context for 3D mosaics survey. The aim of the mosaics survey is the production of a full-scale representation (scale 1:1) useful for the documentation and for the restoration processes. In order to evaluate the optimal photogrammetric/computer vision workflow in this work three different surveys have been done for three mosaics with different size and location. Two of these are stored at Regional Archaeological Museum “Antonino Salinas” in Palermo (Italy) and the other one is stored at Regional Archaeological Museum “Baglio Anselmi” in Marsala (Italy). The research has allowed to show the potentiality and the issues of photogrammetric/computer vision approach for the 3D mosaic documentation.

Guido Zavattoni
Weighing coins in the kingdom of Sardinia 1750/1790

Measuring the mass of coins is an important tool in today numismatic archaeology, but the weighing of coins is as old as the coins themselves, due to the people’s need to ascertain their intrinsic value.

Benedetto Carroccio
Influence of striking praxis and chemical corrosion in weight variations of a big sample of Syracusan bronze coins

The Poseidon’s head/Trident “small flan” bronze coins of Hieron II of Syracuse (275-215 BC) had different proposals of chronology. 2 big hoard of 2,229 pieces overall of these coins were analytically studied. Their weights have great fluctuations but this is not a sign of a long time issue because the same fluctuations are frequent in pieces produced in the same time from the same pair of dies. Parallels to the different conservation of the coins of the 2 hoards are little variations of their medium weights and also a respectful cleaning not produced relevant variations in their weights. The fluctuations of the weights of contemporaneous coins are signs of “al marco” striking. Their chronology was very restricted, probably in 215-214 BC.

Marianna Spinelli
Weight variations in Lokroi Epizephirioi bronze coins: reduction of the standard or striking "al marco"?

This paper proposes some observations on the weights of the Lokrian bronze coinage, so far little studied by researchers. Through a careful analysis of the series, aided by the sequence of the coinages that I studied recently in a doctoral research in progress, I have observed many cases of degradation of the coins weights of the same issue. The fact that this oscillation was often observed in coins struck practically contemporaneously from the same pair of dies or from the same obverse die only is not a proof of standard’s reduction within the same issue but of a generalization of “al marco” striking, which we have to be taken into account when we define the metrological system of the Lokroi mint and its relation with the tablets of the local sanctuary of Zeus Olympian tables and other Magna Graecia mints.

F. Perciante, E. Rizzo, G. De Martino
The informative contribution of the geophysics in the preventive archeology for the knowledge, the protection and planning of restoration project: the case of the Grange of Ventrile

Nowadays the use of the geophysical introspections has entered completely in the methodologies of archaeological inquiries, aimed not only to the discovery or to the spatial definition of possible buried archaeological evidences, but also in the description of a possible state of conservation. The utilization of these non-invasive investigations, perpetrated also in the Italian legislation about the preventive archaeology, permits so to know better the investigated asset and the contiguous territory. These informations help to plan better all the activities concerning the protection interventions and the restoration of real estate and the territorial planning. This contribute illustrates the data of a particular type of intervention, where to the process of planning action aiming to the protection and to improvement of possible buried archeological evidences, under a structure that is already a real estate (Grange of Ventrile), has been added a wider cognitive project for a territorial planning.

Paola Calicchia, Patrizio Verardi, Lucilla Di Marcoberardino, Sara De Simone
Frequency Resolved Acoustic Imaging in the Audio Frequency Interval: Panel Paintings

In panel paintings the peculiarity of the substrate, due to the hygroscopicity of the wood, and the great variety of configurations determine their high sensitivity to the environmental conditions. An accurate evaluation of the structural damage may highly benefit their preventive conservation. We investigate the new application of a nondestructive and low-cost technique, a frequency resolved acoustic imaging method in the audio frequency interval, in the panel paintings’ diagnostics of the structural damage. Three case studies are here proposed, showing very different features in terms of substrate configuration and conservation state of the painted film. A selection of acoustic images are presented, showing the potential of this method to reveal the effects of different causes of deterioration.

Elisabetta Garau, Vincenzo Pascucci, Luca Sanna
The Salvennor Project

The integrated use of different methods of survey (photogrammetry, laser scanner 3D, geophysical survey) plays an important role in the Salvennor project (Sardinia). It is used to: outline the extension and, partially, the plan of the monastery related to the San Michele di Salvennor church, otherwise known solely from archive sources; analyse the walls and initiate a virtual reconstruction of the monastic complex; optimise excavation strategies.

J. R. Plaisier, A. Lausi, L. Nodari
MCX: a beamline for non-destructive X-ray diffraction experiments used to study stained glass windows

The MCX beamline at the synchrotron Elettra is the general purpose diffraction beamline that is well suited for non-destructive and innovative X-ray diffraction (XRD) experiments in the field of cultural heritage. A comprehensive study of the alteration products in grisaille paints was recently performed at the beamline. Such a study is very important to understand the complex processes involved in the deterioration of this type of glass decoration. An exhaustive characterization of these products and so a full understanding of the mechanism of their formation may lead to the development of new protective materials for conservation and restoration. XRD experiments at the MCX beamline allowed us to recognize the alteration products on the grisailles surface and to propose a mechanism for the formation of alteration patinae. Here we present the beamline and its capabilities by showing an example of the study on grisaille paints.

C. Rispoli, S. F. Graziano, V. Guarino, A. De Bonis, C. Di Benedetto, R. Esposito, T. Budetta, V. Morra, P. Cappelletti
Characterization of ancient mortars: preliminary results from Villa del Pezzolo, Sorrento Peninsula, Italy

This study deals with the characterization of ancient mortars from Villa del Pezzolo, a Roman villa located in Seiano (Napoli - Campania, Italy), dated from 1st century B.C. to 3rd century A.D. During the A.D. 79 Vesuvius eruption, the villa was destroyed and then rebuilt twice, in the second and third centuries A.D. (Aucelli et al., 2015). The goal of this work is to improve the knowledge of Roman construction techniques by means of detailed microstructural and compositional examination of a) cementitious binding matrix and b) aggregates, to point out: provenance of raw materials, secondary minerogenetic processes, mortars’ mix-design. This research was conducted in collaboration with the Superintendence of Archeological Heritage of Campania. The first results confirmed that Roman engineers extensively used local geomaterials such as volcanic and sedimentary aggregates mixed with lime. The presence of leucite and garnet let us hypothesize the provenance of the volcanic aggregate from the Somma-Vesuvius complex.

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