The Pertosa Caves, today also known as the Pertosa-Auletta Caves, constitute an important karst system in the Campania region (southern Italy). Crossed by the waters of a river that re-emerges on the surface, they have an overall development of about 3 km. Thanks to the width of the entrance, the excellent location along a natural communication route through the mountains and the natural availability of water directly on the site, the initial part of the cavity was frequented by humans, without interruption, from prehistoric times to the Middle Ages. During the protohistory, in particular, the moment of most marked human presence is recorded in the cave. In this phase an extensive pile dwelling system was built on the waters of the underground river. The system was probably created to make the location, subject to frequent flooding, suitable for human settlement. This structure today constitutes an archaeological unicum not only in Italy but throughout Europe. We briefly analyze its general characteristics providing the results of a radiocarbon dating campaign which allowed to assess the occupation phases of the different contexts and the life span of the wooden artifacts, which came to us in a very good state of preservation. Radiocarbon data allowed to assess the chronological range of the human frequentation of the caves and to date the exceptionally well preserved underground pile dwelling system.

The Committee on Missing Persons in Cyprus (CMP) is a bicommunal committee with the mandate to locate and identify the skeletal remains of 2002 persons who were reported missing during the inter-communal fighting of 1963–64, as well as the events of July and August 1974. During the periods of conflict, several archaeological sites and old cemeteries were used as primary burial sites, among several other types of burials, as they were easily accessed by the persons involved in the interment and little effort was needed to conceal the bodies. The relatively large post-mortem interval and the generally poor post-mortem preservation of the skeletal remains poses an additional challenge in the forensic examination process and the identification of the remains, particularly in the absence of a context or other associated artifacts/evidence. Between 2016 and 2020, the CMP has been collaborating with CEDAD to clarify the relevancy of several cases by using radiocarbon dating. The CMP submitted 139 cases to CEDAD out of which 112 were determined as not linked to the 1963–64 and 1974 events and then not relevant for the CMP project. For the remaining samples radiocarbon dating was used to determine death age.

The method of determining the biobased carbon content in liquid fuel samples is standardized, but different laboratories use different protocols during sample preparation and perform the measurements using different machines. The accelerator mass spectrometry (AMS) laboratories use different combustion, preparation, and graphitization methods for the graphite production for the spectrometric measurements. As a result, the intercomparison between the laboratories is inevitable to prove precision and accuracy and to demonstrate that the results are comparable. In this study, we present the results of an intercomparison campaign involving three 14C accelerator mass spectrometry laboratories. Five samples were used in the measurement campaign, including two biocomponents (fatty acid methyl ester, hydrotreated vegetable oil), one fossil component (fossil diesel), and two blends (mixtures of fossil and biocomponent with 90–10% mixing ratio) in the laboratories of CEDAD (Italy), ETH (Switzerland), and INTERACT (Hungary). The results presented by the laboratories are comparable, and all three laboratories could determine the biobased carbon content of the samples within 1% relative uncertainty, which is acceptable in the scientific, economic, and industrial fields for biocomponent determination.

The stratigraphic succession of the Mar Piccolo basin (Gulf of Taranto, Southern Italy) is well known in the scientific literature dealing with the last interglacial since its morphological evolution is influenced by sea level changes during Late Pleistocene-Holocene. The local Holocene sea level history is well known thanks to data deriving from peat and ash layers identified in different sediment cores obtained underwater and in coastal areas. Peat sediments are frequently interlayed with muddy-sand beds rich in Cerastoderma glaucum (Poiret, 1789). In the literature of the Mediterranean basin, AMS 14C dating on C. glaucum is widely used also in paleo-environmental reconstruction because this bivalve is considered an useful marker of sea level, though in lagoonal systems, large age offsets have been reported in different areas. Due to the availability of precise chronological and geochronological markers, in order to validate the use of C. glaucum in paleo sea level reconstruction, AMS 14C dating campaign was carried out on this bivalve deriving from several cores drilled in the Mar Piccolo basin and its nearby areas. Nineteen AMS 14C dating analyses carried out on C. glaucum sampled from different sediment cores up to a maximum of 30 m from the seafloor are presented. These results show an inconsistency of the ages in relation to a sea-level rise reconstruction model. The interpretation of the data was performed after the estimation of the local age offset calculated by analyzing six live samples, collected in 2017 in Mar Piccolo and in Croatia, and two samples dated to 1968–1969. The results show that for both the classes of samples (2017 and 1960s) an age offset ranging from 600 to 800 yr can be estimated.

Combined dendrochronology and accelerator mass spectrometry radiocarbon (AMS 14C) dating analyses were used in order to date an old living tree named Italus, growing in the Pollino massif in Southern Italy. Wiggle match AMS 14C dating analysis was performed on a 320-yr-long floating chronology obtained by cross-dating four wood cores extracted from the exposed roots of the tree. Following this approach, an age for the tree of ≈1230 yr was estimated. This age makes Italus the oldest living tree in Europe. High-resolution 14C dating analyses performed on single rings extracted from the tree stem allowed us to identify the 993–994 CE large excursion in atmospheric 14C concentration (Miyake event) revealing for the first time its presence in the Mediterranean basin.

In this paper, we present the results of the accelerator mass spectrometry radiocarbon (AMS14C) dating campaign performed on samples selected from different levels in Grotta Romanelli (Castro, Italy). Grotta Romanelli is one of the key sites for the chronology of Middle Pleistocene–Holocene in Mediterranean region. After the first excavation campaigns carried out in the first decades of the 1900s, the cave has been systematically re-excavated only since 2015. During the last excavation campaigns different faunal remains were selected and submitted for 14C dating in order to confirm the chronology of the cave with a higher resolution. Isotopic ratio mass spectrometry (IRMS) measurements were also carried out on faunal remains.

The absolute chronology of Early Bronze Age in the Levant has been the object of a major revision (Regev et al. 2012a), which implied an increase of at least two centuries in respect of traditional chronology. Such a shift back was based upon two sites (Tel Yarmouth, Megiddo) which were the backbone of the “reform,” but actually do not offer complete sequences for the whole EBA. This was the weakest stone of the revision, together with a partial understanding of stratigraphy/contexts from where samples were taken. Tell es-Sultan/Jericho in Palestine was included in this study, as this prominent archaeological site provided well stratified 14C dates for EBA. Its stratigraphy, established by Kathleen M. Kenyon in the 1950s, was reappraised by the Sapienza University of Rome–Palestinian MOTA-DACH joint Expedition (1997–2018). Published 14C dates were reanalyzed along with new samples from carefully stratified and published archaeological contexts, measured by the CEDAD Laboratory (University of Salento, Lecce, Italy). They provided absolute dates connected with stratigraphy useful to double-check the proposed High Chronology. EBA stratigraphic periodization at Jericho suggests a more cautious approach and keeps a multi-based chronology more consistent with a comprehensive historical reconstruction of the Early Bronze Age in Syria-Palestine and Egypt.

The determination of the proportion between the biogenic and the fossil-derived fraction in carbon dioxide emissions from industrial stationary sources is a relevant aspect in the frame of the worldwide efforts to reduce greenhouse gas emissions into the atmosphere. In this field the 14C-based method has gained importance over the years and has been included in standard protocols accepted at both the national and international levels. The advantages of the method, based on the large difference in terms of 14C signature between fossil and biogenic carbon, are reviewed as well as some critical aspects related to its application. In particular the results of a study aimed at validating the method by analyzing synthetic gas mixtures produced in a dedicated plant and with a tuneable proportion between fossil and biogenic carbon dioxide are presented.

A new sputtering ion source has been installed at CEDAD (Centre for Dating and Diagnostics) at the University of Salento in Lecce, Italy. The installation of the new ion source, capable of accepting both solid and gas samples, required significant modifications of the existing low energy injector of the accelerator mass spectrometry (AMS) system. The new ion source is connected, through an in-house designed gas handling interface, to an elemental analyzer which combusts the samples to carbon dioxide and splits the gas into an IRMS system and also to the gas feed line of the ion source. This arrangement allows the simultaneous measurement of C, N content (in the EA), carbon and nitrogen stable isotopic ratios by IRMS and radiocarbon (14C) by AMS on samples with masses in the microgram range. The results of different tests performed to find optimal operational conditions and to improve the system performances are presented. The performances of the system as a function of the diameter of the glass capillary used to feed the source and the pressure of the gas mixture in the syringe are also presented. The achievable precision and blank levels are discussed together with the results obtained in environmental studies.

Archaeological surface surveys carried out near Salve in southern Italy led to the identification of about 90 stone mounds spread over an area of about 100 ha. Systematic archaeological investigations allowed to identify the mounds as funeral structures with some having megalithic features. In the necropolis, both the inhumation and cremation rituals are evident, in some cases within the same mound. This article presents the results of an accelerator mass spectrometry (AMS) radiocarbon dating campaign carried out on different kinds of samples recovered from several structures: unburned and cremated bones, charcoals, and organic residues extracted from pottery sherds. The results allowed to assess the chronology of the site and to shed new light on the different funeral practices in Copper Age southern Italy.

Grotta della Monaca is a karstic cave in Calabria (southern Italy) that plays an important role in reconstructing the oldest strategies for the acquisition of mineral resources in the Mediterranean. In fact, systematic archaeological excavations carried out by the University of Bari allowed the identification of intense prehistoric mining activities aimed at the exploitation of iron and copper ores. Archaeological evidence suggests different phases of frequentation of the cave spanning from the Upper Paleolithic, Neolithic, Copper and Bronze ages up to the Middle Ages. In order to establish an absolute timeframe for the different phases, a radiocarbon dating campaign was carried out and the results presented in this paper.

Accelerator mass spectrometry (AMS) radiocarbon analyses were performed on biobased unsaturated polyester resins in order to assess the potential of the method for the determination of the bio-fraction. Different resins were synthesized in the laboratory with different proportions of raw materials of biogenic origin, and analyzed both in the liquid and in the solid form. As a preliminary step of the study, both the biobased and the fossil-derived raw materials were analyzed in order to determine their 14C content. A comparison of the obtained results with the expected ones allowed us to investigate the potential of the 14C method in this field as well as to address some still open issues such as the levels of uncertainty and accuracy as related to the calculation procedures, the correction for isotopic fractionation, and the effect of the presence of volatile components in the analyzed materials.

Various samples extracted from human tissues (with different radiocarbon turnover rates) of a post-bomb human body were submitted to accelerator mass spectrometry (AMS) 14C dating: hair; a cortical fraction of a skull bone; a trabecular fraction of a pubic symphysis; and enamel extracted from permanent teeth with different dates of formation were analyzed. The analyzed samples showed varying 14C concentrations corresponding to different times of formation or different turnover rates. The implications of the results in forensics studies are discussed.

The San Lorenzo Cathedral of Alba is a Romanesque church (rebuilt in Gothic epoch) located in northwest Italy. Since 2007, this church has been subjected to renovations and archaeological excavations that led to the finding of the lower part of the basin and the water drainage pipe of a baptismal font of unknown age. Thermoluminescence and radiocarbon dating have been carried out respectively on some ceramic elements and lime mortar samples used in both the pipe and basin of the font. Thermoluminescence results suggest that some of the bricks may have been reused from previous structures while 14C results suggest that the font was built between the 9th and the 11th centuries AD, most probably in the 10th century AD.

Radiocarbon dating was first applied to historic lime mortars during the 1960s. However, despite the relative simplicity of the technique in principle, a number of subsequent studies have highlighted important aspects that should be considered. One of the most significant of these challenges arises from sample contamination by carbonaceous substances such as incompletely burnt limestone and aggregates of fossil origin containing “dead” 14C. More recent studies have shown that in the majority of old lime-based mixtures the contamination problem can be avoided through selection of pure lime lumps. These particular types of lumps are believed to originate from areas where the lime is incompletely mixed with the aggregate. It has been demonstrated that even a single lime lump can provide sufficient material for a 14C date of the mortar from which the lump was taken (Pesce et al. 2009). This paper describes the practical challenges associated with location, extraction, and preparation of 4 lime lumps extracted from 2 new sites for 14C dating. These include distinguishing the lime lumps from other lumps present in the matrix and the removal of material surrounding the lime lump. The coherence of 14C dating with other archaeological information on the chronology of historic sites is highlighted through case studies.

Analytical methods based on particle accelerators are widely used in cultural heritage diagnostics and archaeological sciences from the absolute dating of organic materials by means of radiocarbon accelerator mass spectrometry (AMS) to the analysis of the elemental composition of a wide range of materials (metals, obsidians, pottery) via ion beam analysis (IBA) techniques. At CEDAD (Centre for Dating and Diagnostics), the accelerator facility of the University of Salento, AMS 14C dating and PIXE (particle-induced X-ray emission)-PIGE (particle-induced gamma-ray emission) compositional analysis in external beam mode are combined to study certain archaeological materials. We present a review of the combined application of these analytical methods in the study of casting cores of the Riace bronzes, 2 classical Greek statues of extraordinary importance for the history of art.

In the sample preparation laboratory of CEDAD (CEnter for DAting and Diagnostics) of the University of Lecce, a protocol for the quality control of bone samples based on infrared spectroscopy has been set up. The protocol has been recently developed as a check-in test with the aim to identify the presence of collagen in the samples, assess its preservation status, and determine whether the submitted bone samples are suitable for accelerator mass spectrometry (AMS) radiocarbon measurements or not. We discuss in this paper the use of infrared-based techniques to identify the presence of “contaminants” such as restoration and consolidation materials, humic acids, and soil carbonates, which, if not removed by the sample processing chemistry, can be sources of exogenous carbon and can thus influence the accuracy of the 14C determinations.

Bone samples recovered in well-defined and previously dated archaeological contexts were intentionally contaminated, submitted to the standard method for collagen extraction and purification, and then characterized by means of Fourier transform infrared (FTIR) spectroscopy analyses performed in attenuated total reflection (ATR) mode before being combusted, converted to graphite, and measured by AMS. The study shows that the ATR-FTIR technique is an extremely powerful method for the identification of both the collagen and its contaminants and can supply important information during the selection and processing of samples to be submitted for 14C dating.