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The paper illustrates the results of a non-invasive characterisation of pigments and their mixtures in the pictorial surfaces of the wall paintings (10th century) found in the Byzantine church of Palazzo Simi in Bari (Italy). The investigation techniques included portable digital polarised microscopy, fibre optic reflectance spectroscopy (FORS) and X-ray fluorescence spectroscopy (XRF). Data comparison supported the recognition of red and yellow ochres, green earth, vine black, minium and Egyptian blue. The presence of some pigment mixtures demonstrated the recurrence of specific technical expedient used by local medieval artists in order to simulate more expensive pigments, which enabled contribution to the understanding of the valuable artistic tradition of the Apulian Middle Age. Both for purposes of conservation and fruition of the site, which is not always accessible, and due to the complexity in taking suitable photographs for the representation of results, the latter was performed on orthophotos extracted from a digital photogrammetric 3D model of the whole archaeological site. By means of chromatic overlapped layers, an interactive compositional map of the pictorial surfaces was produced.

The introduction of agricultural practices fostered the development of specific technologies for the new subsistence practices and the production of new artefacts. Pyrotechnological structures such as ovens are part of the Neolithic equipment and accompanied the spread of agriculture from the Near East across Europe and the Mediterranean Sea. Ovens located within settlements – mainly domed, above-ground structures – have been traditionally linked to cooking and baking. The function is usually deduced from techno-morphological traits, although experimental approaches or ethnoarchaeological observations have often been used. This article aims to demonstrate the effectiveness of the multidisciplinary approach to understand the function of fire structures. An integrated methodology that combines archaeological analysis, archaeometry, and experimental archaeology has been applied to study the underground ovens of the Early Neolithic site of Portonovo (Marche, Italy) dated to the sixth millennium BCE. Samples of hardened sediment of archaeological ovens’ inner surface and selected pottery fragments were analysed through X-ray powder diffraction to estimate the temperature reached. A life-size replica of an underground oven was then created to perform firing experiments, including pottery firing. Samples of the oven’s walls and experimental vessels were analysed with the same method, and the values were compared. Our results indicate that the Portonovo ovens are potentially multifunctional structures, built for about 700 years, always with the same technique exploiting the natural soil’s insulating properties.

During the Neolithic period, near the North-Eastern coast of the Gargano promontory (Apulia Region, Italy), an important network of mines represented the most ancient European example of systematic exploitation of primary chert sources. These high-quality raw materials were traded between prehistoric communities living on both sides of the Adriatic Sea. However, the Gargano promontory is not the only area of the Apulia Region with chert sources. Secondary sources of the Tavoliere plain deposits and primary sources of the Southern Apennines must be considered in addition to the Gargano chert-bearing limestones. This paper provides an overview of chert sources distribution in the Gargano and Tavoliere plain through a chert sources map based on up-to-date geological and archaeological information. The map represents the first lithic procurement mapping in the Region and it is a very useful tool for planning sampling activities and detect the potential chert sources exploited in Neolithic times. The map was used for sampling pebbles near the coast and inland of the investigated area. A non-destructive multi-parametric protocol for chert investigations (NM-PCI) method was applied to all the collected secondary samples. The results were compared at first with those of the Gargano mines. The output of the partition around medoids (PAM) procedure shows, as a general trend, that primary sources are well grouped, while secondary sources show less clear compositional fingerprints. However, the features of the coastal and inland pebbles are quite different.

Northern Apulia has primary and secondary chert sources which were exploited in prehistory. During Neolithic period, on the north-eastern coast of the Gargano promontory, an important network of mines represented one of the most significant primary chert sources in the Adriatic area. However, easily accessible secondary chert sources are available in the Tavoliere plain in several synthems from the southern Appennines chain to the Gulf of Manfredonia. This work provides an overview of chert sources distributed in the Gargano and Tavoliere plain by means of a combination of up-to-date geological and archaeological information. Moreover, the lithic industries of eight Early and Middle Neolithic settlements were sampled in order to understand the procurement strategies of chert or tools used by communities settled in the Tavoliere plain. A non-destructive multi-parametric protocol for chert investigations (NM-PCI) method was applied to all the collected Gargano mines and secondary chert from the Tavoliere area. The results obtained demonstrate a high percentage of secondary chert used in the investigated sites, and the exploitation of mined chert essentially for the production of blades. In this latter case, provenance from the mines of Maiolica Fm is more frequent than that from mines of Peschici Fm. The polygenic nature of the pebbles occurring in the different synthems is the consequence of different sedimentary histories, as witnessed by the difference in the lithological array between inland and coastal synthems, and makes difficult any attribution to a specific source. If on the one hand these results further testify the circulation of mined Gargano chert in the Tavoliere plain in the Early Neolithic, on the other hand they demonstrate that the secondary coastal pebbles, especially those of southern Gargano lithotypes, were largely used, even in inland settlements. Moreover, these results suggest the exploitation of other primary cherts of the southern Gargano. This underlines the importance of further archaeological and geological investigations to better understand the exploitation and circulation of chert in Northern Apulia and in the Adriatic area.

Notarchirico (Southern Italy) has yielded the earliest evidence of Acheulean settlement in Italy and four older occupation levels have recently been unearthed, including one with bifaces, extending the roots of the Acheulean in Italy even further back in time. New 40Ar/39Ar on tephras and ESR dates on bleached quartz securely and accurately place these occupations between 695 and 670 ka (MIS 17), penecontemporaneous with the Moulin-Quignon and la Noira sites (France). These new data demonstrate a very rapid expansion of shared traditions over Western Europe during a period of highly variable climatic conditions, including interglacial and glacial episodes, between 670 and 650 (i.e., MIS17/MIS16 transition). The diversity of tools and activities observed in these three sites shows that Western Europe was populated by adaptable hominins during this time. These conclusions question the existence of refuge areas during intense glacial stages and raise questions concerning understudied migration pathways, such as the Sicilian route.

A nondestructive multiparametric protocol for chert investigations (NM-PCI) was developed to provide objective criteria for raw material procurements and provenance investigations of archaeological cherts. For this purpose, macroscopic and mesoscopic characteristics (structures, textures and paleontological contents) were used to describe the main visible chert features as well as colourimetric and geochemical data acquired with portable devices. Data handling was performed by means of cluster analysis multivariate statistics, with an appropriate selection of algorithms to process and visualize mixed data matrices (partitioning around medoids (PAM), t-distributed stochastic neighbor embedding (t-SNE)). The protocol was applied to chert samples from the Gargano Promontory (Italy, Apulia) mining complex located in the districts of Peschici, Vieste and Mattinata. These mines, exploited for approximately four millennia, constitute an exceptional prehistoric record of mining archaeology and, above all, a key tool to understand the Neolithisation process throughout the Adriatic region. A map of the primary and secondary chert sources of the Gargano Promontory was produced to manage field sampling of mine structures. Waste materials were selected for the geologic samples of the five mines. Due to their inaccessibility, the samples from two mines consisted exclusively of waste materials. The NM-PCI proved able to discriminate most of the analysed mines and is well suited to provenance investigations of archaeological lithic industries. Compared to previous geochemical studies, the nondestructive method proposed here improves geological resolution, allowing the discrimination of cherts within the same formation.

Routine pottery analyses (optical microscopy, X-ray powder diffraction, X-ray fluorescence) and digital image processing of polarised light photomicrographs were used to answer questions on the provenance and technology of pottery assemblages belonging to Late Acacus hunter–gatherers (ca. 10,200–8000 cal BP) and Pastoral herders (ca. 8300–4650 cal BP) from Takarkori rock shelter (SW Libya, central Sahara). This integrated analytical approach on potsherds was combined with the characterisation of local clayey sediments to identify different local and proximal sources for coarse and fine sediments exploited for pottery production. Two main fabric groups (i.e. Q* and QF*) were identified among the analysed potsherds, where the sediments from the Takarkori area are compatible with the quartz-dominated fabrics (Q*). The local fabric QVe shows evidence of dung addition. Pottery with plutonic non-plastic inclusions (QF*) points to provenance from the southern edges of the Tassili n’Ajjer and is more frequent in Late Acacus and Early Pastoral layers. New insights into pottery production and circulation between Early Holocene Saharan hunter–gatherers and Pastoral communities, as well as into modes of occupation of Takarkori rock shelter, are provided.

The issue of clay processing concerns both provenance and techno-functional ceramic investigations. In the former, the compositional/textural modification of clay alters the petrofacies expressed by the ceramic body and causes a change from the raw material in terms of bulk chemical and mineralogical composition and petrographical features as well. In the latter, identifying the signs of clay processing will provide information on the steps of the chaine operatoire and on the technological choices made to adjust paste plasticity and to avoid failures in the following stages of manufacture. Several examples of clay processing were considered, encompassing deliberate addition of natural and artificial temper and clay mixing, other than fractioning and homogenisation to prepare the forming stage. The expected effects of mineral, vegetal and animal tempers on the paste and on the fired body were outlined. Finally, some analytical guidelines are provided to identify clay processing, using the most common analytical methods. Optical microscopy and electron microscopy provide the main contribution to identifying most of the processing practices on the clay, whereas bulk methods provide indirect evidence that may alone be insufficient to prove the occurrence of a specific transformation, as well as to detect homogenisation features. However, only a careful and multidisciplinary investigation of the ceramic body will help reveal the actions of the chaine operatoire and to test archaeological models in a sound bottom-up perspective.

This article belongs to the Special Issue Low Binder Concrete and Mortars., The present study explores the effect of activating solution concentration (4, 6 and 8 M NaOH) on mechanically and thermally pre-treated carbonate-high illite clay (LCR). Pastes were prepared with an alkaline solution/clay (S/B) ratio of 0.55, which were cured at room temperature and relative humidity > 90% in a climatic chamber. At two and 28 days, compressive mechanical strength was determined, and the reaction products were characterised by X-ray Powder Diffraction analysis (XRPD), Fourier-transform infrared spectroscopy (FTIR) and Scanning Electron Microscopy - Energy Dispersive X-ray spectroscopy (SEM/EDX). Results obtained showed that the presence of reactive calcium in the starting clay induces co-precipitation of a mix of gels: An aluminium-enriched C-S-H gel (C-A-S-H) and a N-A-S-H gel, in which sodium is partially replaced by calcium (N,C)-A-S-H. Pastes prepared with higher (6 or 8 M) activator concentrations exhibit a more compact matrix than the ones prepared with 4 M NaOH. The findings show that the use of a 6 M NaOH solution yields a binder with two days compressive strength >20 MPa and 28 days strength of over 30 MPa., The research was also partially funded by the Spanish Ministry of the Economy, Industry and Competitiveness and ERDF under project BIA2016-76466-R.

Grotta dei Cervi (Apulia, Southern Italy) is the most important European figurative art site for its Neolithic red and brown paintings found in the various galleries of the cave. It was frequented with particular intensity between an advanced phase of the Early Neolithic (first half of the sixth millennium BCE) and continued up to the end of the Bronze Age (last centuries of the second millennium BCE). Among the more than thirty thousand finds, some ceramic shards had black residues on them. These residues were sampled so that molecular and isotopic investigations could be carried out. GC–MS-MS and EA–IRMS after fractionation of the samples allowed us to identify bitumen on some archaeological potsherd remains and to identify its geographic source by comparison with geological samples from Majella and Selenice, two deposits located respectively in Italy and Albania and known to have been exploited since Neolithic times. All the bitumens from Porto Badisco correlate with each other and with the Selenice geological samples. Isotopic fingerprints strongly support the biomolecular evidence and confirm the Albanian origin of the archaeological bitumen. The data presented herein provide the first evidence of export and trade of raw bitumen across the Adriatic Sea from Selenice to Apulia during the Neolithic age thus bringing back to the fifth millennium BCE the transport of bitumen across the Adriatic Sea in the central Mediterranean area.

The paper presents archaeometric analyses (OM, XRPD and XRF) of Greek imports, Greek-type pottery, local reference materials of Orientalising Period (7th century BC) from the modern city of Policoro (Basilicata), in the area of ancient settlement of Siris/Polieion along the Ionian Sea coast. The 34 potsherds can be divided into eight different fabrics for their composition and grain-size distribution. Fabrics IC, ICP, ICC and ICA (n = 27) can be ascribed to the use of a Ca-rich clay, while fabrics QA, IGC, Q and IA (n = 7) to the use of a Ca-poor clay. Pottery made of calcareous clay can be associated with four clay samples from the local marine Plio-Pleistocene clay and fluvial deposits, with significant elutriation as inferred from its very fine texture and chemical variability. Pottery made of non-calcareous clays shows very different non-plastic inclusions (mudstones, chert and quarzarenitic as well as calcareous clasts) which suggest non-local production, with different imports from Greece, such us Corinthian amphorae, Subgeometric pottery and surprisingly also firing pots (chytrai). The Ca-poor samples show a general low to medium sintering (500

Digital image analysis has recently emerged as a powerful tool for the analysis of the ceramic thin sections. By producing quantitative data, it increases the usefulness of ceramic petrography to address archeological questions. Despite several works considering digital image analysis to study archeological ceramic materials, so far, no work has been proposed to evaluate the possibilities of optical microscopy (OM) image analysis for classification and modal analysis, knowing its advantages and drawbacks, as compared to scanning electron microscopy (SEM) image processing. In this work, we propose an algorithm to count the mineral inclusions correctly classified by OM image analysis with respect to SEM images. The proposed algorithm is based on a matching mechanism applied to the regions of interest (ROIs) detected in the OM images according to the corresponding ROIs as detected in the SEM images. Moreover, a comparison with point counting on the same OM images is also provided to evaluate the pros and cons of each method. Two Late Acacus (Mesolithic) potsherds (8900–4200 BP) are considered as case study for modal analysis to identify and classify quartz, feldspars, and carbonate aggregates as mineral inclusions.

The present study focuses on the assessment of the effects of different activation methods on carbonate-rich clays, to understand the mineralogical differences originated and to exploit such information to industry for traditional and innovative applications, especially as a precursor for alkali activated binders. Illite carbonate-rich clay samples were subjected to thermal activation in ox/red atmosphere between 400 and 900 °C, mechanical activation (grinding for 5, 10 and 15 min) and to a combination of such treatments. Mineralogical and textural changes in the activated samples were evaluated through X-ray powder diffraction, Fourier transform infrared spectroscopy and thermal techniques. The activated samples with the highest content of amorphous phase underwent leaching tests in a 3 M NaOH solution by means of inductively coupled plasma-mass spectrometry. The application of the three processing routines, yielded three types of activated clays with different leaching modes of Si, Al, K and Ca: (1) high energy grinding preferentially delaminates clay minerals and reduces the grain size of calcite. K leaching reaches the highest values; (2) thermal heating at 800 °C increases relatively the Si/Al solubility ratio, but the absolute concentrations of these elements are equal or lower than those obtained from ground clays. The relatively higher leaching of Ca is influenced by the formation of non-stoichiometric and poorly crystalline Ca-silicates and -aluminosilicates; (3) high energy grinding combined with heating treatment yields an extended amorphisation, mainly at the expense of clay minerals, with the highest leaching of Si and Al, and the lowest of Ca. New formed K-feldspars inhibit the concentration of K in alkaline solution.

In Upper Nubia (currently northern Sudan), the art of making pottery has a very ancient and durable tradition, dating back to the early Holocene and preceding the introduction of a food-producing economy. Ethnographic case studies have demonstrated that this tradition has been preserved in many areas of the country. This paper presents a comparative study of ancient and modern traditional ceramics from four prehistoric sites at Sai Island, in the river Nile, and a present-day workshop located in the nearby village of Abri. The aim of the study was to investigate any diachronic changes in the selection of clayey raw material and the technological processes of the manufacturing sequence. The study combined macroscopic and analytical approaches and examined a large set of ceramic and local clay samples by means of petrographic (OM), mineralogical (X-ray powder diffraction; XRPD) and chemical (X-ray fluorescence; XRF) analyses. The resulting data underline a remarkable continuity in raw material sourcing and composition, as well as in many technological processes, from the ceramic assemblages dating from Abkan cultural horizon ( c . 5500 BCE) until to the present-day production in Abri. This continuity emerged after a preceding discontinuity, indicated by a different selection of clay raw material and tempers in the oldest production dating to the Khartoum Variant horizon ( c. 7600–4800 BCE).

The results discussed in this paper represent an initial overview of the Mid-Late Neolithic Serra d’Alto pottery of the Murge area. A petrographic comparison of pottery samples from various contexts (caves and settlements) demonstrate a local production in every Neolithic archaeological site considered here. The frequent occurrence of the same fabrics in different contexts suggests the circulation of technological models. Ongoing research at a larger number of Neolithic sites in the same area will confirm or refute the preliminary observations presented here.

The present work analyses the effect of mineralogy, microstructure and firing temperature on the effective thermal conductivity of traditional hot processing ceramics. Samples prepared with two quartz-rich kaolinitic clays (BAR1 and BAR2), a fine kaolinitic clay (ARG) and a glaucophane-rich clay (SIF), were fired in the range between 950 and 1350 °C. The effective thermal conductivity is principally affected by the porosity of the body. Mullite further improves the thermal conductivity of BAR1 and BAR2 ceramics, while in ARG samples cristobalite is correlated with the increase in thermal conductivity. In SIF ceramics, the higher densification and the formation of spinel, pyroxene and hematite results in a higher conductivity compared to the other samples. The amorphous phase improves the ceramics' thermal conductivity since it seals voids between particles. In samples in which quartz exceeds 50 wt%, the ceramics' thermal conductivity decreases because of fissures and detachment zones formed after the α-β quartz phase transition. Finally, functional conclusions are drawn on traditional cooking pot and Medieval glass crucibles.

Ceramics are among the most studied findings, one of the best markers for providing technological and functional information in archaeological contexts. Their chemical-mineralogical characterization allows to answer a large number of historical-archaeological questions about classification, provenance, production technologies, trade routes, economic exchange, etc. The best methodological approach not only integrates morphological-stylistic studies to the archaeometric ones, but also includes a synergic instrumental strategy aimed both to take advantage of each different analytical technique to the best of its potentiality and to over step the problems connected to the preciousness and uniqueness of the objects. As far as the mineralogical and petrographical composition of preindustrial ceramics is concerned, its determination is crucial to answer provenance and technological issues like raw materials procurement and the production processes in this respect, equivalent firing temperature, redox atmosphere during firing are important factors that help in understanding the relevant mineralogical and micro-structural transformations. In this paper, we illustrate how an integrated approach of analytical techniques, tested on different classes of ceramics – pottery with spathic calcite, Apulian red figure pottery and technical ceramics – can provide answers to archaeological questions.

The aim of this paper is to present preliminary data on the composition of the Mid-Upper Eocene chert visible in massive outcrops in the Jebel Zawa valleys, in the Dohuk province of the Northern Kurdistan Region of Iraq. Large chert nodules were systematically extracted from open-air outcrops and natural karst galleries, and employed to produce large blades, known in literature as “Canaanean blades”, from the end of 4th to the mid-3rd millennium BC. Knapping workshops have been identified, evidence of a complex technological organization which served to produce prepared cores and blades to be distributed in the region. Our work highlighted the statistical variability of chert composition at intra- and extra valley scales. The variables discussed in this study were determined by following an integrated multi-parametric protocol for chert characterization (NM-PCI) which includes macroscopic observation, microscopic description and chemical analyses performed with Raman micro-spectroscopy. The samples studied were collected in three valleys featuring mining activities. The Jebel Zawa mines are currently the only known mining complex in the Tigris region. The reference collection of data derived from this study will thus be of crucial importance in order to understand the exploitation strategies, time-frame and spread of Canaanean technology in the region during the urbanization phase.

A multi-proxy record based on calcareous plankton, dinocysts, pollen, mineralogy and grain size has been acquired from the “Ideale” section, the portion of Montalbano Jonico succession (Southern Italy) that could host the GSSP for the Middle Pleistocene. The direct correlation between marine and terrestrial proxies provides a valuable indication of atmospheric and oceanic connections. The record shows a distinct climate variability well expressed by the vegetational changes, sediment input into the basin and sea surface–water modifications. Biotic proxies indicate that, during the study interval, periods of prevailing subpolar/transitional surface–water conditions were concurrent with steppe and halophytic vegetation. Erosional processes on the hillslopes and terrigenous supply, during these periods, were likely favored due to reduced arboreal vegetation, as attested to by sediment composition and pollen assemblages. Temperate/subtropical surface water conditions were concomitant with prevalent expansions of thermophilous arboreal plants and moister conditions on land, which likely promoted chemical weathering leading to an enhanced supply of kaolinite and smectite in the basin. A relationship between mineral content and the nature of the outcropping units in the source area, as well as sea-level fluctuations, has also been considered. A well-defined period of polar–subpolar water incursion, ranging from 793.2 ka to 788.1 ka, matches the major expansion of steppic vegetation on land and the increase of terrigenous supply into the basin. It likely represents the local response to North Atlantic ice-rafted debris deposition. Short-lived warming/cooling episodes punctuate the latest part of MIS 20 and are tentatively correlated with analogue climate phases predating MIS 1 inception. Full interglacial conditions of MIS 19c, lasting 10.6 kyr, started at 784.3 ka and were characterized by warm, oligotrophic and stratified surface–waters coupled with forest expansion, suggesting prevalent warm and humid conditions on land. A potential sapropel-like interval is identified within MIS 19c and correlated to i-cycle 74. The MIS 19c/19b transition is marked, at 773.2 ka, by the reestablishment of millennial-scale variability, similarly to North Atlantic marine and ice-core records. The results improve the paleoclimate framework of a Middle Pleistocene reference section and add further insight regarding climate development across MIS 19 and on potential similarities with its closest Holocene analogue.

Carbonates in clay based ceramics produces higher sintering at lower firing temperatures, but may cause lime spalling, affecting the physical and mechanical behaviour of the ceramic body. The present study investigated the mineralogical and microstructural changes that occur in a kaolinitic clay tempered with different contents of limestone sand with two skewed grain size distributions, after firing. The firing temperatures were set at 500, 750 and 1000 °C. The mineralogy of the fired bodies was analyzed by XRPD and quantitative phase analysis was performed using Rietveld method. SEM–EDS analyses were carried out to investigate the changes in microstructures and the clay/limestone reactivity. The use of sand-sized limestone temper and short firing times induced the formation of non-stoichiometric phases at the clay/limestone boundary, ruled by the lateral variation of CaO activity. The structure and composition of the spinel-type phase (e.g. γ-Al 2 O 3 ), as typical firing product of kaolinite clays, were investigated. Different Ca-silicates and -aluminosilicates (gehlenite, rankinite and larnite) in ceramics fired at 1000 °C are found according to the limestone grain size. Lime spalling already occurs in ceramics fired at 750 °C; it is triggered by coarse calcined grains (σ spalling > σ matrix failure ) and then fractures propagates through finer calcined limestone grains.

The addition of temper was a common practice in the fabrication of traditional ceramics. The present work shows the effects of limestone or quartz added as temper to a kaolinitic clay, on the strength of the ceramic body. With this purpose ceramic tests were prepared adding the 5, 15 and 25% of each temper to a kaolinitic clay. Unimodal skewed grain size distributions (GSDs) for temper were used instead on single grain sizes used in previous experimental works. Furthermore, samples were fired at 500, 750 and 1000 °C in order to analyse the effect of firing temperature on ceramic strength. A correlation between the strength and the porosity, the mineralogy and the microstructure of the samples is presented. Results shows that while temper improves the strength of 500 °C- and 750 °C-fired bodies, it worsens that of samples fired at 1000 °C. Moreover, while at 500 and 1000 °C limestone-tempered materials are less strong than quartz-tempered ones, at 750 °C the opposite occurs. For quartz-tempered bodies fired up to 750 °C, no difference in strength changing the temper GSD is observed, while in other cases the coarser the temper, the less strong the ceramic.

The approach combining image analysis techniques and artificial neural networks is proposed here for automatic classification of mineral inclusions and pores in archaeological potsherds using optical digital images. Particularly, the automatic identification of quartz, calcareous aggregates and secondary porosity is considered. A collection of both plane and cross polarised light images acquired via a digital camera connected to optical microscopy in transmitted light is used. Images concern Holocene potsherds (8900–4200 years BP) from Takarkori rock shelter archaeological site (SW Libya, Central Sahara). The adopted methodology involves different phases. Firstly, image segmentation is carried out to isolate regions corresponding to the interested mineral inclusions and pores. A segmentation procedure based on mathematical operators is customized for each type of inclusions and for pores. Secondly, numerical features are extracted from each segmented region, thus collecting data to perform automatic classification. A modular classifier is considered for classification, which is based on a combination of three two-layer feed-forward neural networks that are trained separately to recognise each class. Experimental results show that the created modular classifier provides high classification accuracy for both inclusions and pores. The classifier was finally applied absent the image analysis phase on new samples to show the effectiveness of the proposed methodology.

Traditional ceramics were commonly produced using a mixture of clay and temper materials, which were added in different percentage according to the craftsman purposes. The present study aims to examine up to which extent some technological parameters (nature, granulometry and percentage of the temper and firing temperature) affect the thermal conductivity of traditional ceramics. With this purpose a kaolinitic clay was tempered either with quartz or limestone belonging to two different granulometric distributions in percentage of 5%, 15% and 25%, and fired at 500, 750 and 1000 °C. Moreover the dependence on firing temperature was studied. Thermal conductivity was measured with a modified Lee's disks apparatus in a temperature range from 120 to 370 °C. It was found that quartz-tempered ceramics are more conductive than the fired non-tempered clay, while limestone-tempered sample are less conductive. Mineralogical and microstructural data are also provided and the influence of the α – β quartz-phase transition on the thermal conductivity of ceramics is discussed.

Fireboxes of two pottery structures, excavated in 2002 at Aventicum (at present Avenches), the capital of Roman Switzerland, were studied to understand their function in the artisan quarter. Twenty-one oriented samples underwent petrographical, mineralogical and chemical analyses to determine the nature of the raw materials and the temperature distribution. Both structures are typologically different and show differing degrees of thermal impacts. Inferred maximum temperatures for kiln Structure 6, as deduced from phase associations, were as high as 1050–1200 °C. Such high temperatures are typically recorded in fireboxes of ceramic kilns. Structure 180 is proposed to have been a drying oven, as evidenced by: (1) its phase associations, pointing to maximum firing temperatures of c. 950–1050 °C, and (2) its unusual shape. Six out of seven clays from the artisan quarter revealed Ca-rich composition, but the Ca-poor one was preferentially used by Roman potters for bricks and clay binders to build the two structures. Such “refractory” clays are obviously better suited to withstand higher firing temperatures and for a longer period than Ca-rich clays.

This paper proposes the application of digital image processing of plane- and cross-polarized light photomicrographs to textural and morphometric analysis as an extension of routine petrographic characterization. The aim is to answer questions on the provenance and technology of quartz- and calcite-bearing potsherds from the Takarkori rock shelter (Libyan Sahara, from around 8900 to 4200 uncal. years bp). Specific processing algorithms run on image analysis freeware (ImageJ) isolate quartz and calcite inclusions to obtain quantitative textural and morphometric data that are useful in identifying different local fluvial and swampy sedimentary environments as sources of sandy clays for pottery.

Fifty oil lamps from the catacombs of ‘Ponte della Lama’ (Canosa di Puglia, second to sixth centuries ad) were analysed to understand the correlations existing between types and fabrics and to determine their provenance. Petrographic and chemical analyses confirmed the archaeological hypothesis of local production of the oil lamps, using fluvial deposits. However, the three samples of oil lamps imitating the African ‘Atlante VIII’ are considered chemical outliers compared to the rest and are supposedly of foreign origin. The extensive and original repertory of lamp types characterizes Canusium as the production centre in the late Roman period.

‘Gnathia’ pottery samples, dating back to the mid-fourth and third century BC, from the archaeological site of Egnazia (Fasano, Brindisi, Italy) have been characterised from the physical-chemical, mineralogical and morphological points of view. Optical and scanning electron microscopy, X-ray energy-dispersive spectroscopy and X-ray diffraction analyses have been carried out on the ceramic body, black gloss, white, yellow and red over-paintings of fragments, with the aim of outlining technological features and defining the nature of coatings and decorations. Analytical results confirm from both a technological and morphological/decorative point of view the close relationship between ‘Gnathia’ pottery and red figured pottery, particularly with the Apulian red figured from which it takes its inspiration. At the same time the experimental results highlight shared characteristics and differences with both Attic and Apulian red figured productions. The biggest difference is in the utilisation of the ‘ingobbio rosso’ layer that covers the ceramic body. This does not seem to be based on aesthetic grounds, as in the case of Apulian red figured pottery, but on application of acquired production processes, since ‘Gnathia’ pottery was made in the same workshops as red figured pottery. Copyright © 2009 John Wiley & Sons, Ltd.

Fifty crucible fragments and 10 fragments of the melting furnace of the forest glassworks of Sudel (1723–1741, Ct. Luzern), were analyzed by petrographic, mineralogical and chemical techniques in order to assess the temperature reached in the melting chamber and to find out which raw materials were used to make the crucibles and the melting furnace. Since the crucibles were used in the melting furnace, the temperature estimations were based on both the crucibles and the refractory fragments, as they were parts of the same system. The temperature range in the melting chamber, estimated by the structural order of the new-formed cristobalite, points to a temperature range between 1350 and 1500 °C. However, three crucible samples recorded extreme temperatures as high as 1650 °C, suggesting very high flame temperatures for wood fuel. The analyzed red bricks were made with local calcium-poor clay. One of them was tempered with refractory fragments, demonstrating an in-house production and the recycling of such a material after its use. The crucibles and the refractory bricks were made with the same refractory clay. The former using unprocessed clay and the latter blending clay with chamotte. A comparison with Siderolithique clayey sand samples from the Swiss Jura, shows strong affinities which may rule out the archaeological hypothesis of an exclusive provenance of such clays from Germany, suggesting an import from the Swiss Jura mountains.

Forty-three sherds of crucible found in the pre-industrial (1699–1714 AD) forest glassworks of Derriere Sairoche (Ct. Bern, Switzerland) were studied in order to determine the nature of raw materials and the technological aspects of their production and use. The samples were analysed using optical microscopy, XRD, XRF, UV–VIS spectrometry and SEM/EDS. The crucibles were produced with local natural clayey sand and fired in two steps. After preliminary firing in a low-temperature furnace (800–1000 °C), the crucibles were brought to temperatures up to 1500 °C within the glass-melting furnace, before adding the glass batch. Using the structural order of cristobalite as an archaeothermometer, temperatures between 1370 and 1500 °C were estimated. The crucible surface shows corrosion by glass and furnace gases. Connections between glassmaking and crucible production are emphasised by this study.

Fragments of the melting furnace and several crucibles of the glassworks of Derrie`re Sairoche are compared with local raw materials. Principal component analysis (PCA) based on the chemical composition and on the grain-size distribution of the archaeological and natural materials demonstrates that the analysed samples were made from the same raw material and that local clayey sands (Hupper, Side´rolithique) were exploited. Availability in situ of good raw materials made tempering unnecessary. Their high melting point (c. 1600°C) allowed good performance in service conditions at temperatures up to 1500°C. Moreover, because of low Fe₂O₃tot concentrations, batch-glass contamination was avoided.

Seventy-one oriented specimens from the pre-industrial reverberatory melting furnace of the Derriere Sairoche glassworks (Swiss Jura) were analysed. During its period of activity (1699-1714), this glassworks produced wood-ash glass of liquidus temperatures up to 1400°C. Textural and mineralogical features point to temperatures around 1500°C in the melting chamber. The inner structure of the furnace shows chemical contamination due to ash, molten glass and furnace gases. These results reveal the pyrotechnological know-how of the glassmakers and prove that the thermal performance of this kind of furnace has been under-evaluated in the past.

This study describes the results of petrographical, mineralogical and chemical analyses carried out on coarse tempered cooking pottery, sampled in the archaeological sites of Herdonia , Posta Crusta (Ordona, FG) and San Giusto (Lucera, FG). From the latter site, two fragments of a pottery kiln, coeval with sherds (IV and V centuries AD), were also investigated. Two groups of clayey sediments of different nature (alluvial and marine) sampled in the neighbouring of the archaeological sites were also analysed. By means of the petrographical analyses, all cooking pottery and the two kiln fragments were grouped in the same coarse tempered group, characterised by the scarce presence of trachytic and glassy fragments, anhedral and zoned augitic pyroxenes and feldspars. PXRD analyses show an abundant presence of quartz and feldspars, followed by pyroxenes and variable quantities of calcite and hematite. Among clay minerals, illite plus muscovite are more abundant than smectite. XRF analyses data display SiO 2 , Al 2 O 3 , Fe 2 O 3 and K 2 O as main oxides, with variable quantities of CaO. In the case of the clayey samples, petrographical investigations on thin-section of psammitic fractions outlined the differences between Argille subappennine (Marine group—Pleistocene) and the alluvial deposits of Celone River (Alluvial group—Holocene). The occurrence of volcanic products, chert, garnet, quartzarenites and limestones in the archaeological materials and in the alluvial samples, let us suppose that cooking pottery was made with alluvial clayey silt. The apparent chemical discordance between pottery and alluvial samples bulk compositions can be due to textural and compositional variability of the alluvial deposits. All ceramics were fired in oxidising conditions, although in many cases a “dark core” was still present. Textural features, observed through petrographical microscope, and PXRD analyses suggested a firing temperature between 600 and 800 °C.

Forty samples of Mid-Late Neolithic “Serra d’Alto” coarse pots (V millennium BC) tempered with spathic calcite were analyzed by petrographic, mineralogical and chemical methods to confirm the hypothesis of widespread technological models of production in different areas in south eastern Italy. The analyzed samples were excavated in different archaeological sites across Tavoliere Plain, Murge Plateau and Bradanic Through areas, namely Masseria Fragennaro, Cala Colombo, Santa Barbara, Sette Ponti, Masseria Candelaro and Grotta Scaloria (Apulia) and Trasano (Basilicata). Almost all the coarse wares were produced using eluvial or colluvial deposits in a carbonatic area tempered with speleothemic calcite. The amount of calcite temper seems to be quantized according to different recipes. LA-ICP-MS analysis of over 30 spathic calcite inclusions per thin section revealed some chemical homogeneity within the same sample and interesting differences among samples from the same site with different pottery fabric. Although the number of the analyzed samples was not sufficient to clearly define characteristic fabrics or reference groups, our preliminary results suggest that the calcite tempered Serra d’Alto coarse ware was produced in different sites, starting from different raw materials and using different processing. The strong similarities in technological processes in different sites clearly show a large network of middle-distance exchange of formal and technological production techniques between many Neolithic communities, located in different geographical areas of South Eastern Italy. LA-ICP-MS analysis of calcite inclusions seems to be a promising route to discriminate the provenance of these ceramic vessels. Keywords: Serra d’Alto ware, calcite temper, LA-ICP-MS.

Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE) has, recently, obtained some promising results in testing the feasibility of mortar radiocarbon dating by means of an ad hoc developed purification procedure (CryoSoniC: Cryobraking, Sonication, Centrifugation) applied to a series of laboratory mortars. Observed results encouraged CryoSoniC accuracy evaluation on genuine mortars sampled from archeological sites of known or independently constrained age (i.e., other 14C dates on different materials). In this study, some 14C measurements performed on genuine mortars will be discussed and compared with independently estimated (i.e., radiocarbon/archaeometrical dating) absolute chronologies of two Spanish sites. Observed results confirm the agreement of the CryoSoniC mortar dates with the archaeological expectations for both examined cases. Several authors reported the possibility of obtaining accurate radiocarbon dates of mortar matrices by analyzing lime lumps: binder-related particles of different sizes exclusively composed of calcium carbonate. In this paper, preliminary data for the absolute chronology reconstruction of the Basilica of the cemetery complex of Ponte della Lama (Canosa di Puglia, Italy) based on lime lumps will also be discussed. Dating accuracy will be quantified by comparing 14C data on mortar lime lumps from a funerary inscription of known age found near the Basilica, in the same study site. For this site, a comparison between absolute chronologies performed by bulk and CryoSoniC purified lime lumps, and charcoal incased in mortars (when found) will also be discussed. Observed results for this site provide evidence of how bulk lime lump dating may introduce systematic overestimations of the analyzed sample while CryoSoniC purification allows accurate dating. © 2012 Elsevier B.V. All rights reserved.

Late Apulian red figured pottery [1] from Egnatia (Fasano, Brindisi, Italy) was studied in order to widen the view on this ceramic class in Southern Italy. Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) provided the samples elemental composition that allowed to make provenance hypotheses. Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrometry (EDS), supplied information about the minero-petrographic features of the objects to better understand their production technology. The set of results highlighted the contemporary presence in the Apulian land in the late 4th century BC of both local and imported finds and showed the existence of two different kinds of local production, the “classic” Attic and a peculiar one, characterized by the application of an engobe layer before the black gloss. Our previous studies resulted in the discovery that an engobe layer, with similar chemical and minero-petrographic characteristics, was present in finds from another site in central Apulia (Monte Sannace). So the discovery of red engobe on fragments from Egnatia, proves that its use was not an isolated occurrence, but was quite common in the production of red figured in Apulia during the Late period, appearing as a peculiar technological mark of Apulian potters.