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Ancient quarries are intriguing archaeological sites, but their detailed recording is complex. This paper presents a cost-effective approach to mapping of the Roman quarry site of Pitaranha (Portugal-Spain). First, aerial photographs were acquired using a radio-controlled digital reflex camera attached to a Helikite, which allowed the acquisition of the necessary low-altitude aerial footage in the very unstable wind conditions above the quarry. Using computer vision algorithms, the resulting set of photographs was semi-automatically transformed into a Digital Surface Model (DSM) and a corresponding orthophotograph. Besides focusing on the acquisition and processing method, this paper evaluates the accuracy of the generated products. The orthophotograph proved to be satisfactorily accurate for 1:200 hard-copy mapping. [ABSTRACT FROM AUTHOR]

This paper focuses on plain, stylistically unvaried pottery from three Late Neolithic sites from the Mondego Plateau, Portugal, and investigates ceramic production and exchange among small-scale prehistoric societies by means of thin-section petrography and chemical analysis (INAA). The results show that the majority of the pottery was made with widely available, granite-derived sedimentary clays, but petrographic differences between fabrics indicate collection at multiple locations within these deposits. Variation in chemical composition is consistent with site-specific sourcing areas, while comparison with data from earlier sites in the Mondego and surrounding mountains suggests that such sources were geographically restricted within the plateau. In contrast, the small percentage of vessels produced with residual clays of metamorphic and intermediate igneous origin, which outcrop over 10 km and 30 km from the archaeological sites, demonstrates that plain pottery did circulate during the Neolithic beyond the funerary sphere. This is the product of the routines of mobility and social networks of Neolithic groups across the wider landscape, which involved the exchange of 'mundane' vessels. Finally, the study demonstrates that micro-regional provenance studies can provide significant insights into prehistoric social landscapes if the data are interrogated beyond simplistic classifications of local and non-local. [ABSTRACT FROM AUTHOR]

The mineralogical fingerprint of both archaeological and geological flint, measuring by Raman microspectroscopy the α‐quartz, and the minor elements was studied. Quartz crystallinity index, by XRD, was calculated in geological samples. An estimation of the degree of crystallinity through Raman analysis could be used to infer quartz crystallinity in archaeological materials. The evaluation of moganite content allowed a better differentiation among Cenomanian flints from different places. It was possible to confirm the correlation between archaeological microfacies M1‐TV with the Torres Vedras Cenomanian flint and warn that the M2 flint preliminary associated to Lisboa region could be from another source area. [ABSTRACT FROM AUTHOR]

In the Iberian Peninsula, the copper metallurgy from the Chalcolithic to the Middle Bronze Age (MBA) was mostly characterized by low arsenic contents. A collection of 53 MBA artefacts from southern Portugal was analysed by micro-EDXRF, optical microscopy, SEM-EDS and Vickers to investigate the metal composition and manufacture. No technological distinction was found between artefacts from domestic and funerary contexts, which were radiocarbon-dated to 2000-1500 cal bc. The arsenic contents of almost 100 MBA artefacts from this region, including the above-mentioned set, have a Gaussian distribution with a high average (3.9 wt% As). Possible explanations are discussed for this distinctive metallurgy at the south-western end of the Iberian Peninsula. [ABSTRACT FROM AUTHOR]

Petrographic analysis of 49 sediments and 63 Neolithic ceramics from eight sites of Estremadura and six sites of the Algarve of central and southern Portugal, respectively, discerned distinct production technologies for each area. Raw materials available near archaeological sites were utilized. Fabrics that do not correspond to regionally available materials, however, indicate imports or migration. This suggests the existence of bidirectional maritime routes rather than south-north only, as predicted in current models of the neolithization of coastal Portugal. Seven ceramics and seven sediments were selected for elemental analysis. The results supported the patterns in the petrographic analysis. [ABSTRACT FROM AUTHOR]

In the Neolithic and Copper Age collective burials of the Portuguese Estremadura, the majority of material culture and skeletal remains are highly commingled, making it difficult for archaeologists to evaluate social status by linking individuals with specific grave goods. In these circumstances, bio-anthropological data about individual life histories offer an additional avenue of investigation into social complexity among prehistoric communities practising collective burial. In this study, stable isotope data were gathered from 81 individuals from seven collective burial sites and one settlement, the fortified site of Zambujal, in order to determine if significant dietary differences exist within or between burials that may point to patterns of social differentiation, both at individual sites and across the region. While in general all of the sampled individuals consumed fairly homogeneous diets based on terrestrial animal proteins and C3 plants, this study found that statistically significant differences in δ13 Cap and δ15 N values exist between several sites, which may indicate socially differentiated consumption of meat and plants. Additionally, statistically significant differences were found in δ15 N values between adults and juveniles, which may either be attributable to protein-restrictive child-feeding practices or physiological processes related to skeletal growth and development. [ABSTRACT FROM AUTHOR]

A multimethod approach using petrography and strontium (Sr) isotopic analysis was applied to determine the geological source of 17 marble artefacts from the Roman town of Ammaia (Portugal). All samples are calcitic, with dolomite, quartz and muscovite as accessory minerals. The marbles are characteristically medium-grained with a maximum grain size (MGS) between 0.98 mm and 1.82 mm, have a heteroblastic texture, and have curved to embayed calcite grain boundaries. 87Sr/86Sr values of marble leachates range from 0.708488 to 0.708639. Comparison with Hispanic and Mediterranean marbles suggests the Estremoz Anticline as the most likely source for the Ammaia marble, especially for architectural marble. This hypothesis is supported by the geographical proximity of the Estremoz marble district and the long and expensive overland transport required for other marbles to reach Ammaia. [ABSTRACT FROM AUTHOR]

Instrumental neutron activation analysis (INAA) has been applied to archaeological samples at the Portuguese Research Reactor (RPI) since 1973, and the number of samples analysed has increased steadily since the mid-1990s. Archaeometric applications of INAA at RPI include the analysis of archaeological ceramics and the stones used in monumental architecture (menhirs) and other historical monuments. A programme of analysis also exists for measuring the precision of and contributing to the certified values of geochemical reference samples. In addition, the study of interference factors is performed to obtain better accuracy in the determination of concentrations of some elements (e.g., corrections for spectral interferences from uranium fission products in the determination of barium, rare earth elements and zirconium). [ABSTRACT FROM AUTHOR]

Since little is known about the cuerda seca technique, our aim has been to complete an initial analysis of 11th-century cuerda seca by studying fragments from the 10th century (Pechina, Almería) and the 12th century (Mértola and Almería), so as to establish the diachronic evolution of this technique. Characteristics specific to cuerda seca ceramic glazes were investigated using scanning electron microscopy (SEM) and quantitative chemical analysis with energy-dispersive X-ray spectrometry (EDX). The chemical compositions of the different-coloured glazes (green, black, yellow and white) have given us valuable indications about the evolution of the technique. The opacification mode and the firing process were also investigated. With the help of cathodoluminescence (CL) and the study of modern ‘cuerda seca ’ glazed ceramics, new hypotheses regarding the number of firing stages, taking into account glaze and paste transformations and their interactions, are put forward. [ABSTRACT FROM AUTHOR]