image/svg+xml155XIII/2/2022INTERDISCIPLINARIA ARCHAEOLOGICANATURAL SCIENCES IN ARCHAEOLOGYhomepage: http://www.iansa.euPetro-Archaeometric Study of Pre-Roman Pottery from the Archaeological Site of Bec Berciassa (Roccavione, Cuneo, North-West Italy): Technological Remarks from Petrographic Study of TempersMaria Pia Riccardi1,2*, Deneb Cesana3, Maya Musa1, Sergio Martini4, Francesco Zucca11DSTA – Università degli Studi di Pavia, via A. Ferrata 9, I27100, Pavia, Italy2Laboratorio Arvedi, sede di Pavia, via A. Ferrata 9, I27100, Pavia, Italy3Soprintendenza Archeologia Belle Arti e Paesaggio per le province di Alessandria, Asti e Cuneo, Cittadella – via Pavia snc, I15121, Alessandra, Italy4Fondazione “La Pietra Lesa”, via Olmazzo 42, I27040, Mornico Losana, Italy1. IntroductionThe Bec Berciassa archaeological site is the most important protohistoric settlement in the Maritime Alps, Cuneo district. It is situated at the confuence of the Gesso and Vermenagna rivers, at 692 metres asl (Figure 1), overlooking the surrounding valleys and lying along transalpine routes that have been used since the late prehistoric period. Before the region was Romanised in the 2ndcentury BC, this hill had long been occupied by the ancient Ligurian tribes from the Late Bronze Age 1550–1200 BC.The discovery of the archaeological site dates back to 1931, when Rittatore Vonwiller identifed and excavated the traces of a “prehistoric village” (Rittatore Vonwiller, 1952). The relevance of the archaeological site for the reconstruction of the history of the territory and its valorisation has been supported by the studies carried out in following years by the Soprintendenza Archeologica del Piemonte (Ferrero, and Venturino Gambari, 2008) and the very recent survey and excavation campaigns (2017–2019) promoted by the Municipality of Roccavione (Cuneo) (Cesana et al., 2018; Rocchietti and Cesana, 2018, Cesana and Padovan, 2019).The study of the pottery individuates an older phase dating back to the Late Bronze Age represented by a small sample of ceramics. At the same time, the chronology of most of this material is homogeneously ascribable to a period between the 6thand the beginning of the 4thcentury BC (Iron Age).Volume XIII ● Issue 2/2022 ● Pages 155–162*Corresponding author. E-mail: mariapia.riccardi@unipv.itARTICLE INFOArticle history:Received: 21stMarch 2022Accepted: 8thAugust 2022DOI: http://dx.doi.org/10.24916/iansa.2022.2.5Key words:ceramicsPre-roman productionnorthern Italyraw materialsproduction technologypetrographyABSTRACTThe petro-archaeometric study of ceramics from the Rittatore excavations, Bec Berciassa archaeological site, was carried out on pottery sherds attributed to an older phase dating back to the Late Bronze Age. This collection represents a small sampling of pottery and the chronology of most of this material is homogeneously ascribable to a period between the 6thand the beginning of the 4thcentury BC (Iron Age). In addition to the archaeometric study, a geological survey highlighted the resources of the area potentially useful for the development of prehistoric communities, including resources that could be used for ceramic production.A thin section study under optical microscope distinguished fve ceramic mixtures. They are mostly coarse-grained, hiatal, and serial-textured, calibrated with the addition of fllers. The fne matrix is homogeneous in composition, although with compositional variations in Fe2O3. Therefore, it is possible to hypothesise a single source of supply. The diferent types of fller can be traced back to minerals and rocks found outcropping within the basins of the Gesso and Vermenagna rivers and thus potentially present as pebbles in their beds. Calc-schists, sparitic calcite, magmatic rocks (granites and aplites), and sericite-schists have been used since the Bronze Age; quartz sandstones and quartzites are only present in Iron Age pottery. At a macroscopic level, all these fller agents are light in colour, tending to white, almost as if the colour and homogeneity of the geological material were a criterion of choice dictated more by tradition and know-how rather than by any particular technological choice.
image/svg+xmlIANSA 2022 ● XIII/2 ● 155–162Maria Pia Riccardi, Deneb Cesana, Maya Musa, Sergio Martini, Francesco Zucca: Petro-Archaeometric Study of Pre-Roman Pottery from the Archaeological Site of Bec Berciassa (Roccavione, Cuneo, North-West Italy): Technological Remarks from Petrographic Study of Tempers156Excavations conducted in 2018 and 2019 unearthed a large number of pottery pieces, nearly 300, but this preliminary study focused mainly on historical fnds from the Rittatore excavations. The ceramic bodies themselves contain signifcant information about the production technology used to make them (Maggetti, 1982; Maggetti, 1994; Freestone, 1995; Quinn, 2013; Montana, 2020). Their detailed study, through a petrographic approach, allows the collection of information concerning the technology followed for the realisation of the mixtures: the raw materials that were used for their production, and where these raw materials were collected.In this study, the petrography of the ceramics was conducted by focusing on the textures of the mixtures and aiming the petrographic reading toward the coarsest parts of the mixture, i.e., both the mono- and polymineralic grains. Quantity, shape, rounding, sorting, and state of conservation of the grains are textural parameters that, when interpreted together with the petrography of the grains, allow us to reconstruct many steps related to the production chain (Eramo, 2020; Gualtieri, 2020).To better understand the manufacturing, we have made a survey of geological materials potentially useful for the production of ceramics. In the area of interest for the archaeological site, there is a geological formation known as “Calc-schists with Green Stones” (or “Calc-schist Complex” Unit), a unit outcropping that extends over the lower slopes of the Vermenagna, Stura and Grana Valleys (Montaldo Calc-schists) and overlaps with that known as Brianzonese Unit (Ormea Unit). The diferent rocks mentioned condition strongly and diferently the hydrography, which therefore difers locally based on the lithotypes encountered by the water and their location: the hydrographic network has its maximum development in the outcropping area of schists (non-porous); correspondingly in the calcareous lithologies (porous), however, the hydrology reduces above 750 m, where these lithotypes dominate, and infltration and an underground circulation prevail, as the surface hydrography almost disappears. All of this has certainly conditioned the anthropisation of the site and not only related to the general conditions of habitability, but especially concerning the availability of water and the exploitation of raw materials. The survey and sampling of geological materials are the basis for establishing technical choices for ceramic production.Two main archaeological questions drove the goals of this paper: What was the production technology of the ceramics of Bec Berciassa? Which raw materials were used?2. Materials and methodsAll samples from the “Rittatore excavations” were analysed with a lens, using a non-invasive approach. The results of this frst survey allowed the identifcation of distinct groups based on the coarse component of the mixture. On this basis, a selection of fnds, representative of each group, was carried out to realise petrographic thin sections. A total of 17 thin sections, polished, were prepared (Table 1).The polished thin sections were studied under optical microscopy using an Olympus BX51 UV polarised light