The University of Bern has set up the new Laboratory for the Analysis of Radiocarbon with AMS (LARA) equipped with an accelerator mass spectrometer (AMS) MICADAS (MIni CArbon Dating System) to continue its long history of 14C analysis based on conventional counting. The new laboratory is designated to provide routine 14C dating for archaeology, climate research, and other disciplines at the University of Bern and to develop new analytical systems coupled to the gas ion source for 14C analysis of specific compounds or compound classes with specific physical properties. Measurements of reference standards and wood samples dated by dendrochronology demonstrate the quality of the 14C analyses performed at the new laboratory.

The SUERC Radiocarbon Dating Laboratory has recently replaced its spreadsheet-based record keeping with a new database program, custom designed to help laboratory staff manage the high throughput of nearly 5000 cathodes in the past year. The system can accept data from a variety of sources in addition to manual entry; experimental results can be uploaded from spreadsheets, while integration with graphitization lines means that graphite yields are automatically recorded. The system is able to pass 14C results directly to OxCal v 4 for calibration, with the resulting plots incorporated into the dating certificates issued to submitters. There are also benefits to submitters, with electronic sample submission both eliminating transcription errors and speeding up the logging-in process, which keeps turnaround times down. For bone samples, data on collagen yields are now stored electronically and are more readily obtainable from the laboratory. The new SUERC Radiocarbon Dating Laboratory database will make a significant contribution to maintaining the high quality of results produced by the laboratory, aiding staff in tracking sample progress, and monitoring quality assurance (QA) samples going through the laboratory, eliminating transcription errors, and making communication easier between laboratory staff and sample submitters.

In the best case, radiocarbon measurements allow artificial objects to be dated with a precision of 10 calendar years when conventional wiggle-matching onto the IntCal09 calibration curve is applied. More precise dating can only be achieved by using annually resolved 14C calibration data, particularly in timespans when there are rapid changes in atmospheric 14C concentration. The recently observed jump in atmospheric 14C concentration of 1.5% between AD 774 and 775, though expected to be rare, is a good example for such a rapid change. We demonstrate by example that is possible to precisely 14C date the cutting year of a timber in the historically important and well-preserved Holy Cross chapel of the convent St. John the Baptist in Val Müstair, Switzerland.

Over 3000 prehistoric bone and antler artifacts, collected in the late 1930s from the former lakebed of Lake Lubāns, are held by the National History Museum of Latvia. This collection is remarkable not only as one of the largest known assemblages of bone implements in northern Europe, but also in terms of diversity of forms. The most elaborately worked objects include harpoons, often with two rows of barbs and spade-shaped bases, which are believed to date to the Late Paleolithic, and to be among the oldest organic artifacts ever found in Latvia. Four broken specimens were sampled in 2011 for accelerator mass spectrometry (AMS) dating, stable isotope analysis, and taxonomic attribution by ZooMS. The results support the interpretation that these artifacts were made from large cervid bones, and date all four objects to the early Preboreal (mid-10th millennium cal BC). The Lake Lubāns harpoons therefore fall in the same period as similar harpoons from Denmark, northern Germany, and Poland, although only a handful of these have been dated directly.

An important advance in the radiocarbon dating of archaeological material occurred in the late 1990s, with direct dating of cremated human remains. A crucial part of the argument was the demonstration that comparable results could be obtained from paired dates of charcoal and calcined bone from the same contexts. Recent studies, however, have noted the influence of carbon from the fuel sources, raising a question over the interpretation of the paired charcoal/bone dates. Here, fleshed modern animal joints were burned with “old” fuel of known age, providing experimental evidence under natural conditions, demonstrating a clear effect of the fuel source on the carbon isotopic composition of calcined bone. In most situations in which branchwood was used as fuel, dates on calcined bone should not show any significant offset, as the wood will be of a similar age to the cadaver. For cases in which old wood, coal, or peat are used as fuel, we expect an offset of some decades/centuries, potentially up to millennia. We observed, however, that the amount of 14C intake from the fuel is extremely variable (from 39 to 95%). A strong correlation between age offset and δ13C values suggests that the latter might be useful in identifying large inputs from 14C-depleted fuels. A level of caution is recommended when 14C dating calcined bone in cases where fuels with an inbuilt age may have been used in the cremation process.

Excavations in the cathedral of Tournai revealed two sepultures, which were identified by the excavators as those of bishops because of their special location in the cathedral. One burial was assigned to Baldwin I, who died in AD 1068, because (1) a ring with the inscription “BAL” was found and (2) a funeral stone with text was present on top of the grave mentioning the name Baldewinus. The second burial probably belongs to Radbot II, who was the successor of Baldwin I, and died in AD 1098. Both burials contained textiles (silk), the skeleton, a wooden pastoral staff, and human hair was still present on the skull of what was presumed to be Radbot II. All the protein-containing materials were degraded and/or contaminated. Standard sample pretreatment methods were not able to remove all the contaminants. Single and double cross-flow nanofiltration of the hydrolyzed protein-containing materials were performed. The sample quality for radiocarbon dating was improved and 14C data revealed interesting and surprising results. The 14C dates of the wooden pastoral staff and permeate femur confirm that the skeleton and tomb belong to bishop Baldwin I. The 14C dates of hair and permeate skull indicate that the skeleton may indeed belong to bishop Radbot II. The younger 14C dates of the wooden pastoral staff and silk samples indicate a postburial disturbance of the site burial during the 12th–13th century.

Since 1994, our team has gained extensive experience applying accelerator mass spectrometry (AMS) radiocarbon analysis for mortar dating, totaling over 465 samples and 1800+ measured CO2 fractions. Several samples have been analyzed repeatedly. The research covers both Medieval and Classical archaeology. We therefore believe our experience can be helpful when developing preparation procedures for different kinds of mortars in different areas and in varying chronologies. So far, the main areas of interest have been (a) the churches of the Åland Islands (in the archipelago between Finland and Sweden); (b) the churches in the Åboland Archipelago (SW Finland); (c) sites in the Iberian Peninsula including Torre de Palma (a Roman village in Portugal); and (d) Rome, Pompeii, and Herculaneum (Italy). Most of the analyses before 2000 were hydrolized in only two CO2 fractions per sample, and reliability criteria were defined on the basis of how well the ages of the two fractions agree with each other. These criteria have proved most helpful in determining the reliability of 14C mortar analyses. Different types of mortar have been investigated, including lime mortars made both from limestone and marble, pozzolana mortars, fire-damaged mortars, and mortars based on burnt shells. Most importantly, separate lime lumps sampled from these mortars have been analyzed sporadically and recently more systematically. The research also includes different types of hydrolysis applied in the pretreatment. In addition to using 85% phosphoric acid (H3PO4), the experimental research includes tests with smaller concentrations of phosphoric acid, and tests based on 2–3% hydrochloric acid (HCl) dissolutions. To characterize the dissolution process, results are presented as age profiles of 2–5 CO2 fractions. In our experience, pozzolana mortars have been difficult to date, and HCl dissolution should be used only in special cases and in complementary tests.

Natural textiles provide suitable material for radiocarbon dating. Short-lived organic matter is usually involved and, if 14C dating is applied to pieces that are stylistically well dated, a better understanding of 14C dating of this type of material can be gained. This study presents some examples of dating that support the stylistic dates. Repeated analyses illustrate the robustness of the standard treatment applied to the textiles.

In 2002–2003, excavations were carried out within the early Iron Age fortified settlement of Motroninskoe Gorodishche in Mielniki (central Ukraine, obl. Cherkassy). The excavations revealed relics of a charred wooden structure in the core of the earth rampart, originally forming the outside fortification line of the settlement. Dendrochronological analysis of 20 charred pieces of the oakwood from the rampart demonstrated that they all represented a single construction phase. However, the chronology produced from them spanned only 62 yr, and the attempts of dating against the European oak standards were unsuccessful. For absolute dating, radiocarbon analysis was conducted on nine samples consisting of 4–8 tree rings, relatively dated and coming from selected timbers, of which dendrochronological sequences defined the above chronology. The wiggle-matching method allowed to determine the two most plausible periods tree cutting: 665–630 or 625–520 BC. The construction date of the rampart outlines the beginning of construction of the fortification system of one of the most heavily reinforced strongholds in eastern Europe raised by the local, settled population for defense against the nomadic Scythians invading from the steppe. Taking into account historic data and other dated artifacts, it may be assumed that the first period, 665–630 BC, would be more probable. This conclusion supports the historical process (crucial for eastern Europe) of migration of the Iranian Scythians from inside Asia and settling in areas around the Black Sea.

Two floating tree-ring chronologies were developed from oak timbers recovered during salvage excavations of a pre-Roman wharf in Este, a prominent center of the Veneti people, who lived in northeastern Italy during the Iron Age. Wiggle-match radiocarbon dating shows that one chronology spans the 10th and 9th centuries cal BC, and that the waterfront was probably built ∼800 cal BC. The second chronology apparently spans most of the 7th century cal BC, and is associated with a phase of construction about 2 centuries after the first. One of the samples gave what appeared to be anomalous 14C results that may best be explained as evidence of a short-term fluctuation in atmospheric 14C level, which can be seen in short-lived samples but is not apparent in the decadal or bidecadal calibration data. Both chronologies cover periods for which there are no other tree-ring chronologies in this region, and could become key to refining the local Iron Age chronology.

During the 1st millennium AD, a fundamental set of changes in ship design, building methods, and sequence of construction took place in the Mediterranean. This process is known as the “Transition in Construction.” Before the Transition, ship hull design was based longitudinally on the ship's strakes (“shell-first”). By about the mid-1st millennium AD, the concept and construction of ship hulls had changed and were based on the ship's frames (“frame-based”). The Transition was a complex, nonlinear evolution. High-precision dating of the construction and service period of ships built during the 1st millennium is essential for elucidating the Transition process. Such dating precision is possible using radiocarbon wiggle-matching and Bayesian analysis techniques. The following study uses these techniques to determine the construction, launch, and final voyage (wrecking) dates of Dor 2001/1, a Byzantine shipwreck from northern Israel that was built based on frames. The results indicate that Dor 2001/1 was likely constructed and launched in the first third of the 6th century AD and was wrecked no later than AD 540. This is one of the earliest frame-based ships found in the Mediterranean so far. Dor 2001/1 is therefore an important shipwreck in understanding the Transition, since it provides evidence that frame-based hulls were already being built by the mid-1st millennium AD, about 500 yr earlier than has been commonly accepted.

Charred plant materials found in archaeological contexts are usually considered the most reliable remains for radiocarbon dating. Usually, seeds and fruits are preferred to wood fragments because their short lifecycle reduces the range of uncertainty of the 14C measurement. A selection of short-lived samples, mainly from barley and wheat, from the Late Roman site of Faragola (SE Italy) were 14C dated; however, the 14C dates obtained were not always consistent with the chronology provided by other archaeological evidence. A careful analysis of all the macrobotanical remains found in each of the dated contexts provides insight into the origin of the plant material, helping to distinguish between in situ and non-in situ material. The 14C dates are reconsidered in the context of findings and the kind of material selected for dating. Using the archaeological context, a Bayesian model was employed to reduce the range of the calibrated date and thereby refine the chronology of the site on an absolute basis.

The radiocarbon dating method was applied to the study of Japanese traditional wooden buildings. The traditional Japanese architecture studied includes the Main Hall of Banna-ji Temple (Buddhist building), Sekisui-in of Kozan-ji Temple (noble house), Hakogi-ke house (farmhouse), and Kawai-ke house (townhouse). 14C dating proved useful as a research method to better understand the history of these buildings and Japanese architecture as a whole.

This study presents accelerator mass spectrometry (AMS) radiocarbon dates and pollen assemblages of 400-cm core sediments collected from the Karekare Swamp in Rarotonga, Southern Cook Islands, to investigate vegetation changes on the island, in particular those induced by human impacts. Eight 14C dates of charcoal and higher plant fragment samples indicate that the sediments accumulated since ∼6.0 cal kBP, with an apparent interruption of deposition (hiatus) from 130 to 132 cm in depth, corresponding to ∼2.8 to 0.7 cal kBP. The appearance of Chenopodiaceae pollen from upland weeds, and Cucurbitaceae and Vigna pollen grains from cultivated plants suggest that human influence existed in core sediments above 130 cm in depth. The increased abundance of Pandanus pollen and monolate-type fern spores also implies the existence of human activity.

This article presents the pretreatment protocols for wood samples processed at the Oxford Radiocarbon Accelerator Unit (ORAU), including recent implementation of a purification method to α-cellulose for non-routine samples. We examine the long-term reproducibility of measurement on wood samples at ORAU through the >1000 14C determinations made on known-age tree-ring standards processed in each AMS wheel since our present High Voltage Engineering Europa (HVEE) AMS system came on-line in September 2002. A discussion of background measurements is also provided.

The updated chronology of the earliest pottery-containing complexes in Siberia and the Russian Far East is presented herein. The appearance of pottery (i.e. the process of Neolithization) in this vast region of Eurasia is discussed based on a model that represents a simple approximation of calendar ages between key sites as isolines. No clear spatiotemporal patterns for the origin and spread of pottery in northern Asia can be observed because pottery-making (unlike agriculture) could have emerged in different parts of the Old World at various times. Before modeling of pottery dispersal is conducted, careful evaluation of typology and technology of ceramics and stone artifacts should be done, in order to avoid the confusing situation when the results of modeling contradict the basic archaeological information.

This article introduces a method of exploratory analysis of the geographical factors influencing large-scale innovation diffusion, and illustrates its application to the case of early pottery dispersal in the Old World. Regression techniques are used to identify broad-scale spatiotemporal trends in the innovation's first occurrence, and regression residuals are then analyzed to identify geographical variation (climate, biomes) that may have influenced local rates of diffusion. The boundaries between the modeled diffusion zones segregate the western half of the map into a Eurasian hunter-gatherer pottery-using zone affiliated by cultural descent to the Siberian center of innovation, and a lower-latitude farming and pastoralist zone affiliated by cultural descent to the north African center of innovation. However, the correlation coefficients suggest that this baseline model has limited explanatory power, with geographical patterning in the residuals indicating that habitat also greatly affected rates of spread of the new technology. Earlier-than-predicted ages for early pottery tend to occur in locations with mean annual temperature in the range approximately 0–15°. This favorable temperature range typically includes Mediterranean, grassland, and temperate forest biome types, but of these, the Mediterranean and the temperate deciduous forest biomes are the only ones on which regression residuals indicate earlier-than-predicted first observed pottery dates.

A case study of the Neolithic comb ceramic site Pezmog 4 of the Kama culture presents a situation when results of radiocarbon dating change long-existing concepts concerning the development of archaeological events. Until the early 2000s, the chronology of the Kama culture, distributed mainly in the Kama and Vychegda River basins, has been based on comparative-typological analysis. Estimates of the age of this culture changed from the 3rd millennium BC in the 1950s to the 1st half of the 4th millennium BC by the 1990s. Research concerning the Pezmog 4 site in the central Vychegda River basin in 1999–2002 has abruptly changed this chronological understanding. The data obtained put the age of the early stage of Kama culture within the time range 5750–5620 cal BC and allowed us to propose the existence of another way of early pottery distribution in the forest zone of eastern Europe at the beginning of the 6th millennium BC. This innovation probably penetrated from the trans-Ural region.

The dolmen known as Shepsi was accidentally discovered on the Black Sea coast (Tuapse region, Russia). Radiocarbon dates show that the classic trapezoidal construction of the Caucasian dolmens with a port-hole appeared in the region as early as 3250 BC. The distinctive structural characteristic for dolmens of that time was a floor slab laid between the side slabs, which were embedded in the ground. The material complex and 14C dates show that this type of dolmen coexisted with the Novosvobodnaya-type of the Maikop culture, located on the northern slope of the main Caucasus ridge. This leads to a new hypothesis concerning the regional origin and further development of the megalithic structures in the western Caucasus.

The corpus of radiocarbon dates run directly on Pleistocene-age human remains in Eurasia (∼120 values, with ∼80 of them found to be reliable) is analyzed and interpreted. The latest Neanderthals are dated to ∼34,000–30,500 BP (∼38,800–35,400 cal BP). They probably coexisted with the first modern humans at ∼36,200–30,200 BP (∼42,500–32,800 cal BP) in the western and central parts of Europe. The earliest direct 14C dates on modern humans in Eurasia are ∼34,950–33,300 BP (∼40,400–37,800 cal BP). A paucity of 14C dates corresponding to the LGM is evident for Europe, but Asia perhaps had larger populations during this timespan. The main criteria for the selection of bone/tooth material for direct 14C dating as now widely accepted are (1) the collagen yield (generally, 1% or more) and (2) the C:N ratio (within the 2.9–3.4 range).