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Archaic Roman painted antefixes, architectural slabs and louteria from the Palatine Hill in Rome, Italy, were studied by non‐destructive and micro‐destructive methods: Portable X‐ray fluorescence (XRF), micro‐Raman spectroscopy, optical microscopy, scanning electron microscopy with energy‐dispersive spectroscopy (SEM‐EDS) and X‐ray diffraction (XRD). The investigation enabled the characterization of raw materials and ceramic technology, providing insights on provenance. In fact, similarities were recognized with terracottas from the neighbouring Etruscan Veii. The analysis of pictorial layers revealed the use of Fe‐ and Mn‐based pigments, as well as the identification of more precious pigments on worthy pieces. The research intended to support the archaeological discussion about the frame of the nascent city of Rome, also in relation to the coeval Etruscan culture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combined non-destructive analytical approach using portable instrumentation • Complementary techniques and multivariate analysis allow characterization of pigments • Improved knowledge on pigments production, sourcing and use in 27 BC – 193 AD Rome Polychrome painted plasters from a suburban villa of Imperial epoch were recovered during the 1930s, and are currently exhibited in the galleries underneath the St. John in Lateran Church, Rome. As wall paintings from the Rome area are a rare find, and as the fragments were never subjected to conservation treatments, it was chosen to non-invasively characterize 113 coloured areas, representative of colours and decorative systems. The chemical and mineralogical information collected from this measurement campaign were interpreted in the light of archaeological context (i.e. the high status of the family who owned the villa , the different renovation works that affected it, the identification of decorative systems linked to such works), as well as of published data from contemporary wall paintings in the Rome area. A multi-analytical, non-destructive characterization of the painted surfaces was carried out in situ by means of portable Raman spectroscopy (pRS) and X-ray fluorescence (pXRF), in the framework of a wider project concerning the study of raw materials and paintings of archaeological interest. The combination of pXRF and pRS allowed to characterize the whole palette, as well as to discriminate among different pigments sharing the same key element, and to identify degradation issues. In this context, the use of principal component analysis gave an important contribution to the interpretation of data ant to the individuation and characterization of pigments such as ochres, green earths, lead based pigments, Egyptian blue, cinnabar, Tyrian purple. Calcium and magnesium carbonates are present, as expected, in the plaster, and are often associated with their sulphates and nitrates, and Ca-oxalates indicating degradation. Lead white and bone white have been used. Some peculiar yellow pigments have been identified, such as realgar/pararealgar and Naples' yellow, in addition to ochres. Hematite, minium and cinnabar were all identified, alone or in mixtures. The presence of the precious dye Tyrian purple is very likely, but could not be confirmed univocally. Green earths and complex mixtures of iron and copper compounds were detected. Egyptian blue was used, highlighting different production processes for this artificial glassy material. For the blacks, we hypothesize the use of carbon-based pigments. The obtained data confirms the general palette used by Roman painters, and sheds new light on the materials used in the Lateran area across two centuries, including their provenance and manufacturing. It appears that different earths and ochres were used diachronically, and that the owners could afford very expensive pigments, such as cinnabar and Tyrian purple. [ABSTRACT FROM AUTHOR]

• An artificial neural network for archaeometric studies has been created to facilitate provenance attribution of archaeological ceramics. • The ANN has been trained by clays mixings mathematically constructed based on a reference chemical database of Sicilian sediments. • Test has been performed by querying the ANN with compositional data of pottery found in archaeological sites. Up to 88% correct attribution has been verified. • Merits of NN have been highlighted, comparing the extent of successfully provisional attribution with results achievable by using classical multivariate statistical method. An artificial neural network (ANN) for archaeometric studies was created to facilitate provenance attribution of archaeological ceramics. A multilayer perceptron model (MLP) was applied to construct the network, including only one hidden layer. Moreover, correction parameters based on historical and archaeological evidences were applied to Bayesian probability factor. The ANN was trained by using clays mixings mathematically constructed based on a reference chemical database of Sicilian sediments. The clay mixing takes in consideration compositional variability within the same geological site and the extent of the ceramic manufacture processes. Test was performed by querying the ANN with compositional data of ceramics found in archaeological sites coherent with clays sampling areas. Up to 88% correct attribution was verified, with good correspondence between geological and archaeological contexts. Finally, merits of ANN were highlighted by comparing the extent of successfully provisional attribution with classical statistical methods (PCA and LDA). [ABSTRACT FROM AUTHOR]

Micro-destructive and non-destructive X-Ray fluorescence techniques and scanning electron microscopy coupled with energy-dispersive spectrometry have been applied for the analysis of ten samples of Hellenistic black-varnished pottery, coming from archaeological excavations in Syracuse and Adrano (South Italy, Sicily). Micro-morphological and compositional investigations, together with statistical data processing, have shown several differences among the varnishes of the specimen found in the two sites. In particular, Syracuse varnishes are characterised by a more homogeneous composition and well-defined raw materials, whereas Adrano samples show a higher variability, probably linked to the use of different raw materials and the poorer quality of the varnish as well. The obtained results attest that, as Syracuse black pottery is concerned, the production technique is at an advanced level, whereas Adrano manufacture seems to be less specialised. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: This paper is focused on a spectroscopic study of some pottery shards from an archaeological site in Syracuse (Sicily, Southern Italy), dating back to the Hellenistic–Roman period. Structural characterization was performed at different scales of observation, i.e. from macroscopic to mesoscopic. The main goal was to point out the potentiality of the small angle neutron scattering (SANS) technique as a non-invasive analytical tool in archaeometry, also in conjunction with other, more usual, methodologies. Correlation of experimental data, i.e. macroscopic typology and texture, obtained from petrographic analysis, and radius of gyration and fractal dimension of the interfaces of the mesoscopic aggregates obtained using SANS, together with mineralogical X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, allowed hypotheses to be made on the production technology of the investigated samples. [Copyright &y& Elsevier]