Over the last 30 yr, there has been an ongoing debate on the dates and modes of the earliest colonization of East Polynesia, namely the Cook Islands, the 5 archipelagos of French Polynesia, the Hawai'i Islands, Easter Island, and New Zealand. At least 3 alternative models were proposed by Sinoto, Anderson, Kirch, and Conte, but interestingly all these models basically relied on the same set of roughly 200 radiocarbon dates on various organic materials from archaeological excavations as far back as the 1950s. Some of the models differed by 500–1000 yr—for a proposed initial colonization around the turn of the BC/AD eras, if not considerably later. By comparing the different approaches to this chronological issue, it becomes evident that almost all known problems in dealing with 14C dates from archaeological excavations are involved: stratigraphy and exact location of samples, sample material and quality, inbuilt ages and reservoir effects, lab errors in ancient dates, etc. More recently, research into landscape and vegetation history has produced alternative 14C dating for early human impact, adding to the confusion about the initial stages of island colonization, while archaeological 14C dates, becoming increasingly “young” as compared to former investigations, now advocate a rapid and late (post-AD 900) colonization of the archipelagos. As it appears, the Polynesian case is more than just another case study, it's a lesson on 14C-based archaeological chronology. The present paper does not pretend to solve the problems of early Polynesian colonization, but intends to contribute to the debate on how 14C specialists and archaeologists might cooperate in the future.

When comparing dendrodates and radiocarbon dates, I advocate using the mean value for archaeologically defined data series, as in the usual case, the correct dating is always more precise than the calibrated areas. However, in the extreme gradient of the calibration curve, we must consider the errors. Based on the Corded Ware from the Tauber basin, I put forward a first example in which a contradiction between the archaeological and 14C dating occurs. If one cleanly separates the older measurements from Köln and the younger ones from Heidelberg, the contradiction towards the archaeological dating is canceled out when only the younger Heidelberg dates are taken into account. Regarding the Early Bronze Age, I shall first deal with the cemetery at Singen and will show, using the typology and the horizontal distribution of the graves, how outliers can be identified, thus narrowing the range for dating of the cemetery. The comparison of 2 archaeologically contemporaneous cemeteries in the Neckar basin (Rottenburg and Gäufelden) again results in contradictions between the archaeological and 14C dating. In this case, the contradictions cannot be solved without any new dating measurements. It is recommended that these should be carried out by at least 2 laboratories. Finally, some recommendations are given to archaeologists. In my opinion, 14C dates that are archaeologically unsuitable should be used to check the findings and the archaeological-typological classification. The contradictions should be reported immediately to the 14C laboratory, so that any possible experimental errors can be identified.

The results of a tentative oak tree-ring chronology built from charcoal samples found in Late Bronze to early Iron Age contexts (late 2nd millennium to early 1st millennium BCE) at the site of Tille Höyük in southeast Turkey, and its placement in time, was published in 1993 (Summers 1993). This represented one of the few publications about archaeological dendrochronology for this period and region. However, the dendrochronological sequence and its crossdating have been questioned, including in this journal (Keenan 2002). Here, we critically reassess and revise the dendrochronological positioning of the site's building phases and their place in time by absolutely dating 7 decadal tree-ring sequences via radiocarbon wiggle-matching.

Ideas of Neolithic societies and of the identities of Neolithic individuals changed rapidly during the last decade. The archaeological concept of “culture” implies sequential changes of material culture in spatial and temporal “slices.” The term “society” describes human behavior within social identities, which could produce huge differences in material culture. Ideas of Neolithic “cultures” are no longer valid, as absolute chronological evidence points to overlapping phenomena of material culture and social developments. A combined use of correspondence analysis (to detect similarities and differences in material culture) and radiocarbon data (to identify the chronological character of material culture) exemplifies such an approach in the deconstruction and reconstruction of Neolithic central Germany.

This paper presents and discusses radiocarbon dates of the Corded Ware culture (CWC) from different regions of Europe (mainly from southern and central Germany and southern and central Poland). The main questions addressed are the controversial significance of particular results, the incompatibility of the obtained date sequences, and the “imprecision of the method.” There is clearly the problem of hundreds of dates from different laboratories and performed in different years. A slight difference in the results leads to an “elongated” chronology and acceptance of a model with synchronicity of many cultural groups. The proposed verification of the 14C chronology is connected with both the dendrochronological method and the comparison of dating sequences obtained from particular regions. At present, the most reliable dating scheme for the Corded Ware culture is the one based on the dendrochronological dates of settlements on Swiss lakes; therefore, the scheme must constitute a reference point for 14C analyses conducted for other regions. Due to the typological diversity of materials, however, not every situation allows for this approach. Thus, many 14C grave dates, particularly the results referring to the late CWC phase (after ~2400 BC), remain controversial.

With the introduction of the radiocarbon method in 1949 and the calibration curve constantly improving since 1965, but especially due to the development of the more accurate accelerator mass spectrometry (AMS) dating some 30 yr ago, the application of the 14C method in prehistory revolutionized traditional chronological frameworks. Theories and models are adjusted to new 14C sequences, and such sequences even lead to the creation of new theories and models. In our contribution, we refer to 2 major issues that are still heavily debated, although their first absolute dating occurred some decades ago: 1) the transition from the Mesolithic to the Early Neolithic in the eastern and western Aegean. Very high 14C data for the beginning of the Neolithic in Greece around 7000 BC fueled debates around the Preceramic period in Thessaly (Argissa-Magoula, Sesklo) and the Early Neolithic in Macedonia (Nea Nikomedeia). A reinterpretation of these data shows that the Neolithic in Greece did not start prior to 6400/6300 BC; 2) the beginning and the end of the Chalcolithic period in SE Europe. Shifting from relative chronologies dating the Chalcolithic to the 3rd millennium BC to an absolute chronology assigning the Kodžadermen-Gumelniţa-Karanovo VI cultural complex to the 5th millennium BC, the exact beginning and the end of the period are still under research. New data from Varna (Bulgaria) and Pietrele (Romania) suggest that start and end of the SE European Chalcolithic have to be dated deeper into the 5th millennium BC.

Archaeological excavations at the Syrian settlement of Tell Qaramel have been conducted since 1999. They are concentrated on remnants of the Protoneolithic and early stages of the Pre-Pottery Neolithic period. The settlement has revealed an extremely rich collection of everyday use of flint, bone, and mostly stone objects, such as decorated chlorite or limestone vessels; shaft straighteners used to stretch wooden arrow shafts, richly decorated in geometrical, zoomorphic, and anthropomorphic patterns; as well as different kinds of stones, querns, mortars, pestles, grinders, polishing plates, celts, and adzes.

Excavations brought the discovery of 5 circular towers. Some 57 charcoal samples were collected during the excavations and dated in the GADAM Centre in Gliwice, Poland. The stratigraphy of the settlement and results of radiocarbon dating testify that these are the oldest such constructions in the world, older than the famous and unique tower in Jericho. They confirm that the Neolithic culture was formed simultaneously in many regions of the Near East, creating a farming culture and establishing settlements with mud and stone architecture and creating the first stages of a proto-urban being.

Newly available radiocarbon dates show the early signs of pottery-making in the North Caspian area, the Middle-Lower Volga, and the Lower Don at 8–7 kyr cal BC. Stable settlements, as indicated by “coeval subsamples,” are recognized in the Middle-Lower Volga (Yelshanian) at 6.8 kyr cal BC and the Caspian Lowland at about 6 kyr cal BC. The ages of the Strumel-Gostyatin, Surskian, and Bug-Dniesterian sites are in the range of 6.6–4.5 kyr BC, overlapping with early farming entities (Starčevo-Körös-Criş and Linear Pottery), whose influence is perceptible in archaeological materials. Likewise, the 14C-dated pollen data show that the spread of early pottery-making coincided with increased precipitation throughout the forest-steppe area.

The direct measurement of organic matter included in archaeological pottery may yield a reliable assessment of age. The main problem consists in the identification of possible origins and assessment of distortion for the age of organic inclusions. Our experiments show that shells included in pottery fabrics are strongly influenced by the reservoir effect, which may reach 500 yr or more. Other organic inclusions, such as lake ooze, do not visibly distort the age. The obtained series of radiocarbon dates have been used for the assessing the age of the early stages of pottery manufacture in southern Russia.

The Avellino Pumices eruption was one of the most catastrophic volcanic events of Somma-Vesuvius, which hit prehistoric communities during the Early Bronze Age. In the last 30 yr, several authors reported assessments about its chronology, including radiocarbon datings, but with poor internal agreement and frequently with large experimental errors. A new and more accurate 14C dating of this eruption (1935–1880 BC, 1 σ) was obtained at the CIRCE laboratory in Caserta (Italy) by 3 AMS measurements on a bone sample of a goat buried by the eruption, collected in an Early Bronze Age village at Croce del Papa (Nola, Naples). These results were verified by other measurements on several samples chronologically related to the eruption. Our data show that human resettlement after the eruption occurred rather quickly but lasted only for a short time in areas affected by the volcanic products, like Masseria Rossa and San Paolo Belsito (Nola, Naples), according to 14C dating of archaeological samples collected below and above the eruption deposits. The state-of-the-art chronology of this eruption, emerging from the results obtained in this work as well as from data in the literature, is discussed.

The Bell Beaker is a culture of the Final Neolithic, which spread across Europe between 2900 and 1800 BC. Since its origin is still widely discussed, we have been focusing our analysis on the transition from the Final Neolithic pre-Bell Beaker to the Bell Beaker. We thus seek to evaluate the importance of Neolithic influence in the establishment of the Bell Beaker by studying the common ware pottery and its chronology. Among the 26 main types of common ware defined by Marie Besse (2003), we selected the most relevant ones in order to determine—on the basis of their absolute dating–their appearance either in the Bell Beaker period or in the pre-Bell Beaker groups.

Understanding of processes that determined the expansion of farming and animal husbandry in south-western Europe is hampered by poor chronologies of the early Neolithic in this region. This paper presents new radiocarbon dates, which are used to construct such a chronological frame for a regional group of the most important culture of the early Neolithic in the western Mediterranean: the Cardial culture.

Radiocarbon dating of charcoal >25–30 kyr can be problematic due to contamination from exogeneous carbon and the variable effectiveness of 14C pretreatments to remove it. Bird et al. (1999) developed the ABOx-SC (acid-base-oxidation-stepped combustion) method for removing contaminants from older charcoal samples, which involves a harsher treatment than traditional acid-base-acid (ABA) pretreatments. This method has been shown to considerably improve the reliability of dating old charcoal from sites in Australia, South Africa, Brazil, and Malaysia (Bird et al. 1999, 2003; Turney et al. 2001; Santos et al. 2003; Higham et al. 2009a). Here, we apply the technique to material from 5 Paleolithic sites from Europe and the Mediterranean Rim. For 2 of the sites (Kebara Cave, Israel and Taramsa Hill, Egypt), the ABOx-SC and ABA methods produced similar dates. However, in the case of 1 site, the Grotta di Fumane in Italy, ABOx-SC pretreatment produced significantly older results from those of ABA methods, requiring substantial reinterpretation of the archaeological sequence of the site. The rigorous nature of the technique resulted in a high failure rate for sample pretreatment, and insufficient material survived the pretreatment for dating from Grotte des Pigeons, Morocco or Gorham's Cave, Gibraltar.

In the course of new excavations at the Upper Paleolithic site at Krems-Wachtberg in the loess region near Krems, Lower Austria, a double burial of newborns was discovered in 2005. One year later, a single grave of an infant was excavated nearby. Both graves are associated with the well-preserved living floor of an Upper Paleolithic hunter-gatherer camp with distinct archaeological features and a rich Gravettian find assemblage. Several charcoal samples from different stratigraphic positions were 14C dated with the accelerator mass spectrometry (AMS) method at VERA. The 14C ages confirm the archaeological assessment of the site to the Gravettian time period. According to the uncalibrated 14C ages, the formation time of the living floor is ~27.0 14C kyr BP. 14C data of ~28.6 14C kyr BP determined for an archaeological horizon below the living floor indicate that the location may have been used earlier by people in the Middle Upper Paleolithic.

The presented research involves the analysis and radiocarbon dating of 2 different groups of carbonate mortars, from Kraków, Poland and Hippos, Israel. Differences in composition of the mortars are reflected in different rates of their acid leaching. The Israeli mortars contain carbonate-basaltic aggregates, which may cause overestimation of 14C age. Preliminary processing of these samples (choice of selected grain-size fraction and collection of CO2 released during the first phase of the acid-leaching reaction), enabled us to obtain good agreement between the 14C dates and the age derived from historical contexts. A similar method of preliminary processing was applied to the carbonate mortars of the Medieval building in Kraków. The Polish samples represent carbonate mortars with some admixture of quartz aggregates, suggesting that they would be an ideal material for 14C dating. However, these samples contained white lumps of carbonates, the structure of which differed from that of the binder. These admixtures, possibly related to the hydrological conditions at the site and to the character of the ingredients, appeared modern, and if not removed prior to acid leaching, they could cause underestimation of the age of samples. The 14C dates of the mortars from the walls of the Small Scales building in Kraków are the first obtained for this object, and their sequence does not contradict archaeological indications on several phases of the building construction.

This paper deals with the potentialities and technical and methodological issues associated with the use of lumps of not completely melted lime as material suitable for the radiocarbon dating of aerial lime mortars and plasters. In fact, the identification and selection of single aggregates of unmelted lumps allows one to reduce the possible contamination resulting from external sources of carbon such as “14C-dead” limestone in sand added to the mixture during preparation. This procedure results in the possibility for accurate 14C determinations from single pieces of masonry, supplying important information about the construction phases of historical buildings. The potential of this approach is shown by presenting the results of the archaeological study on the walls of San Nicolò of Capodimonte church (Camogli, Genoa, Italy), where this technique has been successfully applied to obtain absolute ages of different parts of the building. The obtained results were then compared with the information gathered from historical sources and with stratigraphic and other archaeological studies.

The iron dating project Aikarauta has been launched in Finland. This paper presents the results of the preliminary investigations. The ability for radiocarbon measurement by accelerator mass spectrometry (AMS) of iron in Finland has been demonstrated by using coal-produced iron as reference material. An elemental analyzer has been harnessed to measure the carbon content of small iron samples. In addition, we have hypothesized that a fingerprint of the limestone usage in the smelting process is the high Ca content of iron and slag. This has been examined by performing an iron smelting experiment with limestone as flux, by making elemental analyses of ingredients and the resulting slag and iron, and by a 14C analysis of the produced iron. It is possible that limestone dilutes the 14C contents of the produced iron, making its age determination challenging.

In September 2005, an accelerator mass spectrometry (AMS) system based on a 1MV Tandetron accelerator arrived at the Centro Nacional de Aceleradores (CNA). One of the main research programs for this AMS facility is based on radiocarbon. At the same time as the AMS facility was installed and tested, the 14C sample preparation laboratory was designed and set up. A graphitization line that allows the preparation of 5 samples in parallel was designed and built in October 2006. The first months were mainly dedicated to check and optimize all the sample processing. For such a task, several reference samples have been prepared and measured. Since the beginning of 2007, the laboratory has been fully operational and is currently performing as a service for the scientific community. During 2007, nearly 100 unknown samples were prepared and measured in our AMS system. Most of them were for dating purposes, but also other applications were investigated. The performance of the 14C laboratory and dating service will be shown, with some examples as illustration.