A06_P01

Project Radiocarbon: big data and cross-border histories

Griffiths S¹, Bayliss A²,  Brown L³, Carlin N⁴, Evans T⁵

¹Manchester Metropolitan University, Manchester, United Kingdom, ²Historic England, London, UK, ³Historic Environment Scotland, Edinburgh, UK, ⁴University College Dublin, Dublin, Ireland, ⁵University of York, York, UK

The development of radiocarbon dating revolutionised the practice and philosophy of archaeology internationally by providing independent time reckoning. Radiocarbon is the global scientific dating technique because suitable samples and high-precision calibration curves are available internationally. It could provide the potential for a truly internationalised research agenda. As relative processing costs have fallen and Accelerator Mass Spectrometry has reduced required sample sizes, the number of radiocarbon measurements produced annually has increased hugely.

However, the boom in the production of measurements has led to a fundamental problem. Structures for conserving and accessing these data are not matched by data production. International research is impoverished by the lack of interoperability. There are no international datasets that are supported inter-jurisdictionally by national historic environment agencies, with periodic updates to keep them dynamic and scalable. As a result, millions of euros worth of data are being lost, becoming inaccurate, corrupted, or inaccessible, damaging our collective inheritance understanding the archaeological record.

Project Radiocarbon is designed to assemble and validate radiocarbon results along with detailed metadata from across six national jurisdictions on the islands of Ireland and Britain We will produce an open-access digital repository for radiocarbon results and their associated archaeological information making them interoperable, with a commitment to support a live, dynamic resource, which we believe represents a first in radiocarbon big data projects. The project will make a significant contribution to understanding our shared European heritage, and to the management of heritage assets and the historic environment.

A06_P02

When corrosion is useful: the incorporation of ¹⁴C in lead white

Beck L¹,  Messager C¹, Germain T¹, Hain S¹

¹LMC14-ARTEMIS, Gif-sur-yvette, France

Recent studies have shown that radiocarbon dating can be applied to inorganic compounds such as synthetic lead carbonates, cerussite (PbCO₃) and hydrocerussite (2PbCO₃Pb (OH)₂ (Beck et al. 2019; Messager et al. 2020) . Known as lead white, lead carbonates were used as white pigment or cosmetics from the 4th century BC to the 20th century and were formed by the corrosion of metallic lead by vinegar and horse manure up to the 19th c. In order to better understand the incorporation of ¹⁴C in cerussite and hydrocerussite, lead carbonates were produced in laboratory by the corrosion process under various monitored experimental conditions. Lead carbonates were obtained using two types of acid (vinegar containing ¹⁴C vs ¹⁴C free acetic acid) and three types of CO₂ sources (air, horse manure containing ¹⁴C and ¹⁴C free fossil CO2 gas). Twelve different conditions were tested and ¹⁴C was measured in all the corrosion products: lead acetates when CO₂ was absent and cerussite when CO₂ was present. The results show that cerussites carry the ¹⁴C signature of CO₂ produced by the horse manure or from the fossil gas, indicating that vinegar/acetic acid acts as a precursor and horse manure as a reagent to produce carbonates. These experiments demonstrate that CO₂ produced by horse manure fermentation is incorporated into the corrosion products, meaning that the carbonate function of the lead carbonates carries a ¹⁴C signature corresponding to the natural organic matter. This step is crucial for an absolute dating of lead carbonates by the radiocarbon method.

A06_P03

Integrated methodology for the investigation of paintings – The rediscovery of Jan Ruyscher

Fiorillo F¹, Hendriks L²,  Hajdas I³, Huysecom E⁴

¹The Fitzwilliam Museum, University of Cambridge, Cambridge, United Kingdom, ²School of Engineering and Architecture of Fribourg, HES-SO University of Applied Sciences and Arts Western Switzerland, Fribourg, Switzerland, ³Laboratory of Ion Beam Physics, ETH Zürich, Zurich, Switzerland, ⁴Faculty of Sciences, University of Geneva, Geneva, Switzerland

The challenging reconstruction of the history of a painting involves several questions: when the object was made being the easiest one to answer based on scientific evidence, while defining the authorship is more complex.

Within the context of heritage sciences, ¹⁴C analyses are gaining popularity owing to advances in microsamples. The integration of radiocarbon dating on the support, the natural organic binder and lead white pigment, with spectroscopic techniques used to investigate the paint layers, offers a complementary approach to characterise an artwork.

To illustrate its potential, this combined methodology was applied to a case study: a landscape painting bearing the signature of Jan Ruyscher, one of the ‘Little Dutch Masters’ of the 17th century. Radiocarbon analysis of the support dated the wooden panel to the mid-18th century; however, spectroscopic analyses identified titanium white in the paint layers, a pigment put into commerce only in the 1930s.

From an historical perspective, Jan Ruyscher vanished from art history after his death and was rediscovered in the 1930s. The combination of art historical information and scientific findings shed new light on the story of the object; a painting of a less-known painter was made in a specific timeframe, likely following an increased demand of its artworks. The deliberate re-use of an old panel revealed the forger’s intent to deceive.

The methodology provides critical arguments for the identification of a period of creation of the painting, a possible reconstruction of its history, and its classification – in this case, a forgery.

A06_P04

Archaeological site of Vetricella: chronology and anthropic and natural landscapes

Di Cicco M¹, Mantile N¹, Marasco L², Bianchi G², Altieri S¹, Vetromile C¹, Lubritto C¹

¹University Of Campania, Caserta, Italy, ²University of Siena, Siena, Italy

In this paper we show results concerning the chronological and landscape reconstruction of Vetricella (Scarlino, GR) archaeological site,  situated in the centre of the coastal plain crossed by the river Pecora, near Scarlino Castle. The research work  is  based on a multidisciplinary strategy:  the high variety of material remains discovered, as numismatic, ceramics and vitreous finds; archeometallurgical, archeozoological and archaeobotanical studies,  radiocarbon dating and stable isotope analyses permitted to reconstruct the economic and productive activities, datable from at least the 7th to the 11th century. In particular radiocarbon dating of organic remains and mortar sample permitted to recognize the signs of 4 distinct periods of presence, which can be divided into a chronological period between the 7th - 8th century and the first half of the 11th century, due the type of the recovered finds.

Moreover the multi-analytical study permitted to discover the reduced time frame within which the "birth" and the greater development of the site are allocated, corresponding to the end of the 9th and the end of the 10th century.

The project has been realized in the framework  of the ERC (European Research Council) research project “ nEU-Med: Origins of a new Economic Union (7th to 12th centuries): resources, landscapes and political strategies in a Mediterranean region”.

A06_P05

Archeometric research of samples from Huelva La Joya (SW Iberia)

Michalska D¹,  Krueger M², Mrozek-Wysocka M¹, Moreno Megías V³

¹Adam Mickiewicz University, Institute of Geology, Poznań, Poland, ²Faculty of Archeology, Adam Mickiewicz University, Poznań, Poland, ³Departamento de Prehistoria y Arqueologia, Universidad de Sevilla, Seville,  Spain

Samples from the cemetery of Huelva La Joya (Spain) excavated in the sixties and seventies of the 20th century have been analyzed in order to refine the chronology of the grave archaeologically attributed to the early Iron Age. In the grave no. 9 a double burial, cremation and inhumation, accompanying by rich grave goods of local and foreign provenance were found. The radiocarbon dating of selected charcoal fragments was compared with the relative chronology. Samples from the cemetery were carefully analyzed. Selected fragments of charcoals were also identified.

Then, the results obtained for the Huelva La Joya site were compared with the results of ¹⁴C measurements for the archaeological material from the Setefilla site. These results showed that the biconic bowls are much older than originally thought, the oldest ones dating back to the last centuries of the Bronze Age.

A06_P06

Viking or hippie? A leather bag found in a bog in southern Norway

Nadeau M¹,  Zurbach D¹, Rzadczka-Juga I¹, Opheim-Larsen K², Andersen س, Svarva H¹, Seiler M¹

¹National Laboratory for Age Determination, NTNU University Museum., Trondheim, Norway, ²Olav Magnussonsveg 56, Saksvik, Norway, ³Innlandet fylkeskommune, seksjon for Kulturarv, Hamar, Norway

A treasure can be found anywhere, at any time. In 2021, while hiking in the Dovrefjell, Norway, an area which contains snow patches and is often frozen, a young man discovered a well preserved but relatively old, odd looking leather bag in a peat bog. The bag is made of rather thick but very soft leather in natural colour. It has been sewn with thin leather bands and decorated with stiches and metal studs.

The good condition of the bag and the apparent lack of comparative objects from prehistoric times led the local authorities to conclude that it could be as new as the 1970s. The uniformity of the metal studs and the fact that they were not usual decorations support this conclusion. Nevertheless, the young man sent a sample for radiocarbon dating.

The leather sample was cleaned with a sequence of organic solvents before the standard acid-alkali-acid (AAA) treatment. The solvent sequence was applied three times, followed by AAA treatment and ¹⁴C measurement after each step to ensure that all contaminants were removed and that the results did not change. The leather and thread were also analysed by FTIR. Optical microscopy was used to identify the origin of the leather and thread.

We present here the results of the different analyses leading to our conclusion. Far from being from the seventies, radiocarbon results indicate that it might have been the prized possession of someone 800 years before that. However, one could buy it online...

A06_P07

New dating sequence for Andean oracle at Maucallacta; Arequipa, Peru

Sobczyk M¹, Huels M², Rakowski A³,  Olaya Cotera C⁴, Kłaput J¹, Pawlyta J⁵, Sieczkowska D¹, Ziółkowski M¹

¹University of Warsaw, Warsaw, Poland, ²Uni Kiel, Kiel, Germany, ³SUT, Gliwice, Poland, ⁴Independent researcher, Lima, Peru, ⁵AGH, Kraków, Poland

The acheological research related to the Maucallacta site is part of the project carried out since 1996 by the University of Warsaw, (Poland) and the Catholic University “Santa María” (Arequipa, Peru). The Project covers archaeological investigation in the vicinity of the snow-covered volcano Coropuna which was frequently mentioned by chroniclers of the 16th and 17th centuries as an oracle, worshiped since pre-Inca times.The archaeological site of Maucallacta is located approx. 170 kilometers north-west of the city of Arequipa in thesouthern highlands of Peru in District of Pampacolca, Province of Castilla, Department of Arequipa (LS; 3,750 m asl). The architectural complex of Maucallacta, composed of more than three hundred stone buildings, tombs and ceremonial structures. Maucallacta may be considered the principal administrative, pilgrimage and religious center related to the volcano and one of  the most important Inca site discovered in Kuntisuyu, the Fourth Quarter of the Inca State. The ceremonies that took place there are evidenced by extensive deposits containing numerous organic remains, including fragments of camelids bones (lama, alpaca). They were discovered at the foot of the largest square, located on a huge stone platform. The dating of the material (bone fragments) from the individual layers of the stratigraphic deposits allows to obtain new data on the probable sequence of celebrations carried out in this complex.

A06_P08

Dating the Wilson’s Arch complex, Jerusalem: methodological insights

Regev J¹,  Uziel J², Mintz E¹, Regev L¹, Boaretto E¹

¹Weizmann Institute of Science, Rehovot, Israel, ²Israel Antiquities Authority, Jerusalem, Israel

Radiocarbon dating is rarely applied in Classical and Post-Classical periods in the Eastern Mediterranean, as it is not considered precise enough to solve specific chronological questions, often causing the attribution of historical monuments to be based on circumstantial evidence. This research, applied in Jerusalem, presents a novel approach to solve this problem. Integrating fieldwork, stratigraphy, and microarchaeology analyses with intense radiocarbon dating of charred remains in building materials beneath Wilson's Arch, we absolutely dated monumental structures to very narrow windows of time – even to specific rulers.

Most of the dated samples were organic remains extracted from the mortar between the building stones. As the site was filled and covered over the years, microarchaeological methods were used first to verify the identification of the original mortars. Furthermore, hard work was invested to find and identify sufficiently large single fragments of short-lived samples, confirming that each date represents a single point on the calibration curve.

Various construction technologies were used along the 1300 years time span over which the buildings were constructed. As we searched for, identified, extracted, and dated the organic aggregates within the plasters and mortars, very different stages of preservation were identified: in some cases even fresh straw was extracted, while in other materials, the organic remains were extremely fragile. Another aspect to consider is that different building material functions require different technology. The resulting chemical properties of the context affect the preservation state of the material for dating and allows secure dating by chemically definable original material.

A06_P09

Mortar dating of the Stari Most bridge at Otres, Croatia, using data extrapolation

Sironić A¹,  Alajbeg A², Cherkinsky A³, Borković D¹, Barešić J¹, Krajcar Bronić I¹

¹Ruđer Bošković Institute, Zagreb, Croatia, ²Museum of Croatian Archaeological Monuments, Split, Croatia, ³Center for Applied Isotope Studies, University of Georgia, Athens, United States of AMerica

Many different approaches exist to radiocarbon dating of mortar, and there is still no universal recipe that would work in all cases. We experimented with data extrapolation from the dates of CO₂ fractions collected by sequential dissolution. The method was modelled after data obtained from two laboratory mortars. Here we use the same method for dating the archaeological site – the Stari Most (Old bridge) at Otres, Croatia.

The arch of the bridge is still partially preserved, making it possible to walk over the Otres creek even today. Based on cadastral and archive data it can be ruled out that the bridge was built after the beginning of the 19th century. A considerable number of stone bridges in the southern Croatian region Dalmatia were built during the Ottoman rule (16th-18th century), but the way of its construction reveals that the Stari Most bridge does not belong to this period either. Since Roman stone bridges were also built differently, the most probable possibility remains that the Stari Most at Otres is medieval.

The preliminary dating of the bridge places it from the 9th to the 13th century. The preliminary dating correlates the bridge to the neighboring Otres-Crkvina archaeological site, where most of the activities took place between the 9th and 15th centuries. This is the first attempt to date this arch bridge.

A06_P10

Dating by U-Th and ¹⁴C of secondary carbonate deposits: search for validation criteria. Application to rock art at Nerja cave

Pons-Branchu E¹, Barbarand J², Caffy I³, Dapoigny A¹, Dumoulin J³, Medina-Alcaide M^4,5, Nouet J², Sanchidrian Torti J⁵, Tisnerat-laborde N¹,  Valladas H¹

¹LSCE/IPSL, CEA-CNRS-UVSQ Univ. Paris Saclay, Gif-sur-Yvette, France, ²GEOPS, Univ. Paris Saclay, Orsay, France, ³LMC14, CEA-CNRS-UVSQ Univ. Paris Saclay, Gif-sur-Yvette, France, ⁴PACEA, Univ. de Bordeaux, Pessac, France, ⁵University of Cordoba, Geography and Territory Sciences, Cordoba, Spain, ⁶Instituto Andaluz de Ciencias de la Tierra, Granada, Spain

Accurate dating of cave carbonate parietal samples is a real scientific issue that would have a major impact in prehistory. Decorated Paleolithic caves are abundant and most of them contain wall decorations engraved or traced with metal oxides that cannot be directly dated by carbon 14; their chronology is therefore very uncertain. Many drawings are covered with carbonate deposits that can be dated by radionuclear methods making it possible to open a new field of investigation for research on Paleolithic art.

Since almost 10 years, researches conducted at Nerja cave on these carbonate layers permitted to establish validity criteria. To get meaningful chronological information on the carbonate formation above or below the parietal representation and define validation criteria for dating, we i) characterized the mineralogical structure of the samples to verify that they behaved as a close system and ii) combined ¹⁴C and ²³⁰Th/²³⁴U dating methods on the same sample in order to estimate the reliability of measured ages. We will present a review of previously obtained data and new ones.

A06_P11

¹⁴C Dating of historical Japanese musical instrument flute sack

YOKOYAMA M¹,  SAKAMOTO M, Takaya H

¹Kyoto University, Kyoto, Japan

The radiocarbon dating method was applied to the study of Japanese traditional textiles. The Japanese traditional texture studied includes the traditional musical instrument flute sack which is possessed by Japanese Emperor Go-Daigo (1288-1339).

In our previous work, we studied and applied the radiocarbon dating method to one of the oldest Japanese flag  Emperor Go-Daigo possessed. The ¹⁴C dating of this flag was 1463-1528 or 1553-1634.

We launched a research project of Southern-Northern court at Yoshino of Nara, Japan  and clarify blank history of Japan by applying radiocarbon dating method to Emperor's Imperial Treasure in Anou history and folklore museum.