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When dating documents by radiocarbon (14C), what we typically measure is the concentration of the support (e.g. paper, parchment, or papyrus). This can however lead to a possible misinterpretation of results because the support may be older than the writing itself. To minimize such a possible ambiguity, the ideal approach would be direct dating of the ink or color (if organic). Here we propose a feasibility study to date carbon-based black inks when deposited on papyrus, one of the most widespread writing supports used in the past. We prepared test samples, using a commercial papyrus and a homemade black ink, obtained combining modern charcoal fragments and Arabic gum. Even though the ink binder might have represented the best candidate to be dated, we verified by FTIR that the molecular composition of its soluble fraction is very similar to papyrus extractives, thus identifying the residual charcoals recovered after extraction as the most suitable material for the measurement. Enough charcoal material was extracted from the test samples and processed using our new setup optimized for microgram-size samples. The overall experimental procedure was found to be reproducible, and measured 14C concentrations were coherent with the data obtained from larger samples and raw materials.

An innovative protocol for the consolidation of ancient bone remains based on the use of nanometric HydroxyAPatite (HAP) was set up and tested through a multidisciplinary approach. A new protocol for the synthesis of HAP nanoparticles was developed, and the composition of the obtained nanomaterial was investigated through Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD); sizes, shape and morphology of the synthesized particles were studied by Scanning Electron Microscopy (SEM). The consolidation performance was evaluated by testing the new nanomaterial on degraded ancient bone findings. An increase of the mineral density and of the micro-hardness of the bone were observed. The new consolidation method was also tested to assess possible effects on the palaeogenetic analysis and radiocarbon dating on the treated bones. The consolidation treatment does not introduce any contaminations that could affect radiocarbon dating and has no general detrimental impact on the genetic characterization of the skeletal remains. This consolidation procedure represents a more compatible conservation tool with respect to traditional procedures: it has been shown that the treatment is effective, easily-applicable and compatible with post-consolidation analysis.

Lipari, the largest of the Aeolian Islands, is located in the southern Tyrrhenian Sea. Archeological evidence suggests an early human occupation starting from the Neolithic period. The island, favored by its volcanic history, was an important crossroads of cultures and commerce exchanges during prehistory up to Greek and Roman dominations. In this study, we present multidisciplinary analysis results on four skeletal remains from the necropolis of Contrada Diana attributed to the Roman period. By using Next Generation Sequencing technology we identified the biological sex and reconstructed the complete mitochondrial genome for two individuals. We retrieved the first ancient L3e5a lineage that is today present only in North and Central Africa. In addition, a 14C dating of 2,030 ± 45 years BP was obtained for one individual. A previous ancient DNA study has highlighted a genetic link between Sicily and the African continent at least from the Bronze Age. Our results, documenting the existence of contacts between Lipari and Africa during Roman influence, are particularly relevant to better understand the peopling of the Aeolian Archipelago when the island was a sea route of primary importance for the trade in the Mediterranean.

An innovative protocol for the consolidation of ancient bone remains based on the use of nanometric hydroxyapatite (HAP) was set up and tested through a multidisciplinary approach. A new protocol for the synthesis of HAP nanoparticles was developed, and the composition of the obtained nanomaterial were investigated through Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD); sizes, shape and morphology of the synthesized particles were studied by Scanning Electron Microscopy (SEM). The consolidation performance was evaluated by testing the new nanomaterial on degraded ancient bone findings. An increase of the mineral density and of the micro-hardness of the bone were observed. The new consolidation method was also tested to assess possible effects on the palaeogenetic analysis and radiocarbon dating on the treated bones. The consolidation treatment has no substantial impact on the genetic characterisation of the skeletal remains and does not introduce any contaminations that could affect radiocarbon dating. This consolidation procedure represents a more compatible conservation tool with respect to traditional procedures: it has been shown that the treatment is effective, easily-applicable and not detrimental for 14C dating and palaeogenetic analysis.

Infrared spectroscopy allows to reliably distinguish between calcites formed by different processes, e.g. geogenic and anthropogenic calcite. This approach can be used for rapid sample analysis in the radiocarbon dating of mortars. The datable component is represented by anthropogenic calcite, that results from the reaction of calcium hydroxide with the atmospheric CO2 during the hardening of the material. However, different possible sources of contamination can alter the true radiocarbon concentration and can thus make the mortar appearing either older or younger. The preventive identification of the origin of calcite present in the sample allows to measure only anthropogenic calcite, reducing the time and cost of Accelerator Mass Spectrometer (AMS) measurements. Many papers are present in the literature discussing the use of Fourier transform infrared spectrometry (FTIR) with the KBr pellet method, to distinguish the origin of calcite. In this paper, the use of attenuated total reflectance mode (ATR-FTIR) is evaluated since it may present valuable advantages such as non-destructivity, in the perspective of sample reuse for dating.

An innovative protocol for the consolidation of ancient bone remains based on the use of nanometric HydroxyAPatite (HAP) was set up and tested through a multidisciplinary approach. A new protocol for the synthesis of HAP nanoparticles was developed, and the composition of the obtained nanomaterial was investigated through Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD); sizes, shape and morphology of the synthesized particles were studied by Scanning Electron Microscopy (SEM). The consolidation performance was evaluated by testing the new nanomaterial on degraded ancient bone findings. An increase of the mineral density and of the micro-hardness of the bone were observed. The new consolidation method was also tested to assess possible effects on the palaeogenetic analysis and radiocarbon dating on the treated bones. The consolidation treatment does not introduce any contaminations that could affect radiocarbon dating and has no general detrimental impact on the genetic characterization of the skeletal remains. This consolidation procedure represents a more compatible conservation tool with respect to traditional procedures: it has been shown that the treatment is effective, easily-applicable and compatible with post-consolidation analysis.

The LABEC laboratory, the INFN ion beam laboratory of nuclear techniques for environment and cultural heritage, located in the Scientific and Technological Campus of the University of Florence in Sesto Fiorentino, started its operational activities in 2004, after INFN decided in 2001 to provide our applied nuclear physics group with a large laboratory dedicated to applications of accelerator-related analytical techniques, based on a new 3 MV Tandetron accelerator. The new accelerator greatly improved the performance of existing Ion Beam Analysis (IBA) applications (for which we were using since the 1980s an old single-ended Van de Graaff accelerator) and in addition allowed to start a novel activity of Accelerator Mass Spectrometry (AMS), in particular for 14C dating. Switching between IBA and AMS operation became very easy and fast, which allowed us high flexibility in programming the activities, mainly focused on studies of cultural heritage and atmospheric aerosol composition, but including also applications to biology, geology, material science and forensics, ion implantation, tests of radiation damage to components, detector performance tests and low-energy nuclear physics. This paper describes the facilities presently available in the LABEC laboratory, their technical features and some success stories of recent applications.

Due to the fact that the policy regarding the publication of images from the collection of the Papyrological Institute, the owner of the object under study, changed when the article was already in publication, the authors would like to make the following corrections to this paper [...]

The classification and conservation of ancient artworks (belonging to collections) is of important cultural, historical, and economic concern. However, ancient textiles often display structural damage that renders them fragile and unsuitable for exhibition. One of the most common types of damage is linked to erroneous restoration treatments, among which the application of glues to consolidate cuts. Harsh strategies, such as mechanical or chemical treatments, are not suitable since they can cause further impairment of the fabric, whereas mild approaches, like wet cleaning, are often ineffective, as also demonstrated by the present study. Here, we have explored the possibility of using gellan-immobilized enzymes of bacterial origin (Bacillus alpha-amylase) to obtain a satisfactory starch removal from a damaged archaeological tunic-shroud from the Turin Egyptian Museum (Italy), without altering the original yarns or textile fibers. This method, already applied to clean casein-damaged wall paintings, as well as cotton, silk, and linen fabrics, has proved to be optimal for the treatment of a wool burial shroud and to be able to definitively solve fragile textile restoration problems. Moreover, efforts have been made to obtain insights into the artwork: a multidisciplinary approach has allowed to obtain a correct chronological attribution (radiocarbon dating) and fabric fiber characterization (SEM-EDX) as well as shed light on the colored parts and dark stains (FORS+IRFC and XRF). Finally, the evaluation of the type of glue, by Fourier transform infrared spectroscopy, has suggested the best enzyme for glue removal. These results have demonstrated that a mild bio-based approach is a successful tool for the treatment of archaeological textiles in critical conditions.

The 14C technique is well known for the traditional dating but it has very large applications in several fields of research. For example, it allows the investigation on the atmospheric processes and ocean circulation to gain information about past climates. Moreover, the technique finds applications in biomedical and environmental studies. A new original graphite preparation facility has been installed at the INFN Laboratory of Bari (Italy). The CO 2 from the combusted sample is purified using a simple vacuum line set-up. The produced graphite targets are measured using the Accelerator Mass Spectrometry (AMS) at the INFN-LABEC Laboratory of Florence (Italy). In this paper, the preparation line is described in detail and recent results are reported.

At INFN-LABEC (Florence, Italy), a new pretreatment for radiocarbon dating based on chloroform has been recently set up. This method aims to remove the synthetic resins used for artwork restoration, which otherwise could alter the original 14C content. The present study characterizes the efficiency of the process when applied to wood. We have verified whether the effectiveness of the pretreatment depends on the number of extractions in chloroform. We prepared samples by applying different volumes of Paraloid B-72®, one of the most widespread products used in restoration, on poplar wood of known age. Contaminated samples were artificially aged in a climatic chamber. A fraction from each sample was collected before any treatment and after respectively 1, 2, 3, and 4 extractions in chloroform, and 14C dating by AMS, the resin appears to be already removed after the first two extractions. Furthermore, the extracted mixtures of chloroform and possible removed Paraloid were measured by FTIR spectroscopy, the results of which confirmed the 14C results. The efficiency of the pretreatment was also verified on historical wooden materials that had been previously restored. In these cases, a higher number of extractions is required, suggesting a careful approach when dealing with “real” artworks.

In the combustion and graphitization line for 14C-AMS samples used at INFN-LABEC for archaeological and geological applications, samples are burnt using an elemental analyser (EA). Advantages and drawbacks of EAs are known, a drawback being the possibility to introduce some contaminations or memory effects. Different parts inside an EA, e.g. the autosampler and the gas-chromatography column, might in principle be responsible of such problems. During a measurement run some time ago, we measured, indeed, radiocarbon concentration values somewhat higher than usual in nominally blank samples. These “bad” data could be explained by memory effects. By assuming a constant contribution from the sample of the prior combustion, this effect might be corrected: indeed, by repeating cycles of sequential combustions of standards and blanks, we observed a good reproducibility of the amount of contamination from the previous sample needed to explain the results. However, we were obviously unhappy with the fact itself of such corrections being needed, and several tests were performed to identify the source of contamination and eliminate it. Eventually, we succeeded in finding the cause of this failure and in recovering the full performance of the system.

Recently, developments have been made to the external scanning microbeam of INFN-LABEC laboratory in Florence. A new system for mechanical sample scanning was implemented. This system allows us to acquire large maps (up to 20 × 20 cm 2 ), of great interest in the Cultural Heritage field. In parallel, the possibility of using carbon microbeams for experiments, such as, for example, ion beam modification of materials and MeV Secondary Ion Mass Spectrometry, has been investigated. As a test application, Particle Induced X-ray Emission with carbon microbeams has been performed on a lapis lazuli stone. First results for both wide area imaging and external carbon microbeams are briefly reported.

In the last few years some new implementations and upgrades have been made to the external scanning microbeam of INFN-LABEC laboratory in Florence, enriching the existing PIXE, PIGE, BS, IBIL set-up with complementary techniques, when possible allowing for simultaneous multi-technique analyses. We developed a system, compatible with the existing set-up, for the out-of-vacuum detection of the forward scattered particles. This system makes feasible the external-STIM (Scanning Transmission Ion Microscopy) and external-FS (Forward Scattering), now both available at our beamline. Test measurements are shortly presented.

The issue of contamination in radiocarbon dating is well known and can affect not only archaeological findings but also artworks. In the latter case, a possible source of contamination is represented by the products used during the restoration, e.g. resins of synthetic origin like the well-known Paraloid, applied to wood artifacts as a strengthening and preserving agent. In the case of incomplete removal prior to dating, the resins produce an apparent aging of the samples. Mechanical cleaning using traditional tools and the standard pretreatment acid-base-acid (ABA) protocol are not sufficient to remove such contaminants, while the use of organic solvents, in particular petroleum solvents and chlorine-based products, can be effective. However, the most widely used protocol, based on the Soxhlet extraction system, is very time consuming. Here, in the presence of chloroform-soluble applied products, like the widespread Paraloid B-72, this study proposes the use of a new easily operated pretreatment procedure, developed at INFN-LABEC in Florence, based on the use of chloroform (CHCl3) as solvent and on a simple extraction. First, the effectiveness of this procedure was checked by applying it to remove the resin from wood samples of known age, which had been previously intentionally contaminated by applying large quantities of Paraloid. 14C AMS measurements performed on the test samples before and after contamination and application of the proposed procedure proved its effectiveness for removal, while this was not the case when applying standard ABA protocols. Fourier transform infrared (FTIR) spectroscopy analyses also were used to check the removal of contaminants. The new procedure was applied in two case studies: the wood frame of an altar piece from the Renaissance and a painting on canvas from the early 20th century. For both artworks, the use of synthetic resins was documented in restorations performed a relatively long time ago: the wood frame was restored using just Paraloid, the canvas using a thermoplastic polymer soluble in chloroform. Enough time elapsed for the resins to create cross-linking bonds with the original material. Despite this, the results obtained by 14C AMS dating confirm the reliability of the new chloroform-based pretreatment in removing the contaminations. Also in these cases, spectroscopic techniques were used to compare the effectiveness of the ABA and the new treatments in removing the contaminants.