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Corinna Rossi, Francesco Fassi, Cristiana Achille
LIFE Project: evolution of survey techniques along the border of the Roman Empire

This article presents the latest results as well as an overview of the continuous evolution of the survey methods applied to the extreme desert environment of the Kharga Oasis, in Egypt’s Western Desert. The detailed survey of the architectural and agricultural remains of the Late Roman site of Umm al-Dabadib represent the chance to experiment the application of 3D survey techniques to complex objects. The aim of this research is twofold: pushing the available techniques to their limits in order to obtain innovative results, and eventually obtaining a precise and measurable 3D model of a complex and challenging built-up area.

Antonio Profico, Fabio Di Vincenzo, Luca Bellucci, Flavia Strani, Mary Anne Tafuri, Giorgio Manzi
Advances in virtual archaeology: research, preservation, and dissemination

The archaeological and palaeontological record (including human skeletal remains) often bears crack, damage and deformations. The recent rapid development of the diagnostic potentials of “virtual archaeology” has provided innovative tools to manage, study and preserve cultural and natural heritage. These tools include, among others, CT-scans, Laser-scanning, photogrammetry, 3D imaging and rapid prototyping. This approach can contribute to any archaeological context from its discovery to research, preservation, and dissemination. 3D imaging techniques, for instance, substitute physical intervention with a virtual protocol aimed at restoring the original shape of an archaeological item or a fossil specimen. In a similar way, the recovery of digital morphological information can be gathered using data preserved even on a deficient finding through the use of 3D comparative samples. Here we present an extended and updated review about the most innovative protocols applied in virtual archaeology and palaeontology.

Clément Laplaige, Jean-Yves Ramel, Xavier Rodier, Bechir Ben-Rhima
Extraction of linear structures from LIDAR images using a machine learning approach

For extraction and characterization of archeological structures from LIDar data, most studies focus on manual spotting (vectorization) or automatic image processing (IP), while few studies have examined semi-automated methods based on machine learning (ML). In the context of the Solidar project, after trying to use classical image processing techniques, we propose to reflect on elements to be integrated in ML approaches for a better and a more flexible extraction and characterization of archeological structures discovered in the LiDAR datasets. Indeed, the LiDAR data reveal many varied remains over large geographic areas. Manual digitizing of these remains is a time-consuming activity and does not guarantee an exhaustive recognition of features. This article proposes to present: (1) the archaeological context of this work, (2) the searched objects in this study, (3) the first tests and (4) how the data will be processed in the near future.

Elisabetta Di Francia, Ruth Lahoz, Emma Angelini, Sabrina Grassini, Marco Parvis
Pulsed laser cleaning of metallic heritage

The main goal of this study is to design and optimize a low-invasive laser cleaning treatment for metallic cultural heritage artefacts. The treatment should remove the dangerous corrosion products without affecting the original surface of the artefacts. The pulsed laser cleaning process is performed, in this preliminary step, with a near-IR Q-switched Yb:YAG fibre laser on artificially patinated Cu-based reference samples. A morphological and microstructural investigation has been carried out on the specimens submitted to the cleaning process in order to evaluate the effects of the different laser parameters. The optimized laser cleaning procedure will be validated, in a second step, on real ancient metallic artefacts.

Bojana Radojkovic, Slavica Ristic, Suzana Polic, Aleksandar Krmpot, Branislav Salatic, Jovana Orlic, Filip Vucetic
XRF and LIBS Measuring on Metal and Ceramic Laser-Cleaned Surfaces

The use of lasers in the conservation of artefacts plays an important role since its posibilities of safe, efficient and efective cleaning on complex surfaces and wide range of materials. This paper presents the results of the laser cleaning effects on ceramic medieval artefacts originated from archaeological sites from region of Tyre and Sidon, Lebanon and naturally tarnished brass plate (unknown origin). Nd:YAG and Er:Glass lasers were used to clean unwanted layers from artefact surface. Before these investigations, some preliminary analyses were conducted on the comparable contemporary samples. Effects on the laser irradiated zones were investigated by optical and SEM microscopy and EDX analysis. LIBS and XRF were used for the morphological and chemical analysis of laser radiation impact on the examined materials. Also surface 's profile roughness and surface hardness were measured. Some parameters for successfully and safely cleaning of brass surface without degrading the surrounding material were determined.

Andrea Taschin, Paolo Bartolini, Jordanka Tassaneva, Jana Striofa, Raffaella Fontana, Cristiano Riminesi, Renato Torre
THz time-domain spectroscopy: investigation of thin layers of inks

We develop an original experimental procedure and a comprehensive method of data analysis to measure the optical parameters of drawing media in the THz spectral range. The method based on the THz – Time Domain Spectroscopy is applied to recover material parameters on drawing inks deposited on polyethylene pellicles with thicknesses down to tens of micrometers. In particular, we investigated three commercial inks: a red ink (based on cochineal carmine), a blue ink (indigo) and a black ink (irongall). The implemented experimental procedure and numerical method enable us to extract the absorption coefficient and refractive index spectra in an absolute scale, opening the possibility to investigate the material parameters in the THz range with a complete quantitative study.

Eleonora Destefanis, Elena Basso, Gabriele Ardizio
The Cluny Priory of Castelletto Cervo (Biella, Italy): Archaeometric Study of Mortars

The Cluny Priory of Castelletto Cervo (Biella, Piedmont) was deeply investigated from 2006 to 2014, in a multidisciplinary project. This contribution deals with the methodological approach followed for the archaeometric study of mortars, and the results in term of material knowledge and reading of the building phases in a time interval of about a millennium. Petrographic observations combined with microchemical data showed that the local raw materials were exploited during a very long time span: the aggregates are polygenic sands, with a high percentage of volcanic rock grains, coming from the hydric basins of the Cervo River, and its tributary Ostola; the binders are mainly Mg-bearing limes lime, with a strong hydraulic component due to the reaction between the binder and the volcanic grains of the aggregates. A good match between mortars composition and building phases was determined only for some of the earliest phases of the monastery.

M. E. Fedi, L. Liccioli, P. A. Mandò
FTIR spectroscopy as a support for radiocarbon dating: advantages and limitations to identify possible contaminations

One of the fundamental hypotheses the radiocarbon dating technique is based on is the fact that the sample to be dated has to be considered as a close system. However, when we would like to date a finding that has been restored, that hypotesis might be called into question. Any carbon-based material used for restoration has to be completely removed from the sample before the radiocarbon measurement, in order not to alter the results.

Nicolas Garnier, Bastien Dubuis
Looking for ancient wine as gift for the Principe of Lavau (5th c. BC)

The excavations in Lavau brought in light a large monumental necropolis with a burial mound in its center overlying the inviolate chieftain 's grave from the end of the 1st Iron Age or beginning of the 2nd one. In the funerary chamber a rich furniture accompanies the dead: a bronze cauldron containing serving and drinking vessels in ceramic, silver, and bronze, two bronze plates, and a cist. As the inner surface of the cauldron presents visible deposits, a series of samples was taken off from different parts of the cauldron and the local oenochoe. Using a doublestep methodology of extraction and structural analysis by GC-MS, main biomarkers have been identified. The high sensitive and selective method and its efficiency for dissolving particularly insoluble markers from fruits, all owed the identification of coniferous pitch and fermented dark grape juice (red juice). For the first time, the interdisciplinary research of archaeologists and chemists highlight the content of rich vessel used for the funerary banquet.

D. Ciofini, S. Siano
Sub-ablative LQS Nd:YAG laser irradiation effects on cadmium yellow paint layers

On the wake of recent successful applications of LQS Nd:YAG (1064 nm) laser in conservation of modern easel paintings, here, we focus on the study of undesired side effects of the laser treatment that can occur in photosensitive modern paints. Understanding the phenomenology and nature of their alterations has a crucial importance for extending the laser approach in conservation. In the present work, a measurement methodology for characterising the sub-ablative effects of photosensitive paint layers was developed. The analytical approach was refined by considering the example case of cadmium yellow. CdS-based paint mock-ups using different oily binders were prepared and systematically laser irradiated under an epifluorescence microscope coupled to a spectrometer. The latter, image analysis, and ESEM-EDX allowed to collect information on the alteration phenomenology. The method provided underlines the strict dependence of the damage nucleation on the distribution of the pigment within the matrix along with a set of other features of interest for defining and assessing the laser treatments.

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