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Along the value chain (exploration, mining, processing, recycling) generally solid samples of complex matrix and non-stoichiometric composition need to be analysed. Besides spatially-resolved analytics applied to technology development, bulk analytics is mainly used for characterisation of value components. In the search of the best-suited method, there are important questions to answer at first: 1. What is already known about the sample (matrix, stability, solubility, interferences)? 2. What data are needed (quantitative, semi-quantitative or qualitative)? 3. Are the concentrations of the elements of interest at a major, minor or trace level? 4. How urgently are the data needed and what are the financial restraints? Here, two different projects are selected to demonstrate a typical search for fit-for-purpose analytics spanning from commonly available Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to more rarely applied Instrumental Neutron Activation Analysis (INAA). These are two examples of primary and secondary raw materials (intermediate goods and waste), which would open possibilities for side products of critical metals, e.g. REE, PGE, Re, Ga. The first project deals with a natural mineral sample of molybdenite (MoS2) taken from an open pit mine in Kačaran (Armenia) in use for Mo and by-product Re mining. Rhenium is important for catalytic and petrochemical industry, metallurgy, and aviation, e.g. it is used for steel reinforcement in turbine blades for aircrafts [1,2]. The second project focus on secondary raw materials from the non-bauxitic production of aluminium and alumina in Siberia. The analysed materials were taken from different stages of the production process: The final product alumina (Al2O3), waste products like red mud (mainly calcium carbonate and SiO2), sodium salts (e.g. Na2SO4) and anode slag (carbon, Cu-Al alloy, Al) and by-products like wollastonite ceramics (CaSiO3) and soda-potash (K2CO3/Na2CO3). Of course, there are pros and cons of every analytical method (Total Reflection X-ray Fluorescence (TXRF), ICP-MS, INAA) for different samples yielding to clear conclusions about the best-suited method for future analytical tasks. For example in the case of Re, INAA is identified as method of choice for such kind of analysis due to high sample throughput, an easy and quick sample preparation and a low detection limit (0.26 μg/g). References: [1] A. Brumby, M. Verhelst, D. Cheret, Catalysis today. 2005, 106, 166-169. [2] C. Zhan-Fang, Z. Hong, Q. Zhao-hui, Hydrometallurgy. 2009, 97, 153-157.

The natural volcanic glass obsidian is one of the classical objects of archaeometric analyses. Reliable provenancing by means of the highly specific chemical composition, the “chemical fingerprint”, can provide information about trading routes, extension of territory, long-distance contacts and the mobility of prehistoric people. Since the pioneer work of Cann and Renfrew in 1964 [1] various analytical methods have been employed on obsidian samples in order to locate their provenance. The existing data already offers important knowledge about long-distance interactions between prehistoric human populations. However, most applied techniques just show a small part of the element spectrum. Latest studies showed that published results gained by different analytical methods are not consistent due to systematic errors [2-3]. Therefore, the application of three complementary analytical techniques on the same set of raw material samples allows both a better characterization of obsidian sources and a comparison and validation of analytical results. The aim of this multi-methodical approach is to apply in particular: • Ion Beam Analysis (IBA) comprising of Particle Induced X-ray Emission (PIXE) and Particle Induced Gamma-ray Emission (PIGE), • Instrumental Neutron Activation Analysis (INAA), • Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) to detect a maximum element spectrum and to compare element concentrations determined with at least two analytical techniques. This approach should check the accuracy and reliability of analytical results and should show a maximum of compositional differences between European obsidian sources to reveal the most characteristic “chemical fingerprint” composed of more than 40 elements. These investigations are part of a new multi-methodical analytical database called the “Obsidian Least Destructive Analysis Provenancing System” (OLDAPS). This novel scientific approach for provenancing obsidian artefacts found in archaeological contexts contributes to both conservation and prehistoric research by ensuring a minimum of destruction to gain a maximum of information. Besides, it enables to assess analytical accuracies of our archaeometric elemental analyses. For this study, IBA, INAA and LA-ICP-MS measurements have been applied to the most relevant obsidian sources in central and southern Europe. IBA studies have been carried out using the external 4 MeV proton beam of the 6 MV Tandem accelerator of the Ion Beam Centre of HZDR. INAA investigations have been performed in the TRIGA Mark II 250 kW research reactor of the Atominstitut in Vienna. LA-ICP-MS measurements have been taken with the Thermo Element 2 ICP-MS coupled to an ArF gas Excimer laser system at the Aberystwyth University. [1] J.R. Cann, C. Renfrew, Proc. Prehist. Soc. 30, (1964) 111-131. [2] R.G.V. Hancock, T. Carter, J. Archaeol. Sci. 37, (2010) 243–250. [3] G. Poupeau et al., J. Archaeol. Sci. 37, (2010) 2705-2720.

Obsidian ist ein natürliches, vulkanisches Glas, welches bei geeigneter Bearbeitung die Herstellung von sehr scharfen Werkzeugen und Waffen ermöglicht. Auf Grund dieser Eigenschaft war Obsidian einer der begehrtesten und daher weitest verbreiteten Rohstoffe in prähistorischen Kulturkreisen. Die Herkunftsbestimmung von Obsidianen, liefert somit Kenntnisse über ur- und frühgeschichtliche Handelsbeziehungen. Zur Charakterisierung von Obsidianen wird der sogenannte „chemische Fingerprint“ herangezogen, welcher die Bestimmung signifikanter Unterschiede in den Elementzusammensetzungen ermöglicht. Seit der Pionierarbeit von Cann und Renfrew 1964 [1] wurden zahlreiche Analysen mit den unterschiedlichsten Methoden durchgeführt. Die existierende Datenbasis hat bereits wichtige Erkenntnisse über die Verbreitung des Obsidians erbracht, wobei in den häufigsten Fällen nur Teile des Elementspektrums bestimmt wurden. Neueste Untersuchungen haben aufgezeigt, dass bei publizierten Herkunftsbestimmungen mit unterschiedlichen Methoden aufgrund systematischer Fehler nicht direkt vergleichbare Daten produziert wurden [2, 3]. Eine kombinierte Anwendung derAnalysemethoden: • Instrumentelle Neutronenaktivierungsanalyse (INAA), durchgeführt am TRIGA Mk II Forschungsreaktor des Atominstituts der TU Wien • Kombinierte externe Ionenstrahlanalytik: Particle Induced X-ray Emission (PIXE) und Particle Induced Gamma-ray Emission (PIGE), ausgeführt am 6 MV Tandembeschleuniger des HZDR • Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) Messungen, durchgeführt an der Aberystwyth University, Wales, UK auf denselben Satz von Obsidianproben ermöglicht einerseits die Bestimmung eines umfangreichen und aussagekräftigen Elementspektrums, andererseits einen direkten Vergleich der Reproduzierbarkeit und Richtigkeit der Analysenwerte. Mit Hilfe dieser Analyseverfahren wurde eine methodenübergreifenden Datensammlung von Obsidian-vorkommen aus dem europäischen Raum erstellt. Diese Vorgehensweise liefert ein größtmögliches Elementspektrum aus mehr als 40 Elementen und enthüllt die signifikantesten Elemente zur Obsidiancharakterisierung (siehe Abb. 1). Abbildung 1: Elementspektrum von Obsidian aus Demenegakion und Agia Nychia (Melos, Griechenland). Die Kombination von INAA-, PIXE & PIGE- und LA-ICP-MS-Daten liefert einen maximalen „chemischen Fingerprint“ von 41 Elementen. Die Normierung auf eine interne Obsidian-Referenzprobe aus Hrafntinnuhryggur (Island) ermöglicht eine eindeutige Unterscheidung der beiden Vorkommen in den Konzentrationen von Ca, Ti, Sc, Fe und Co. Die unmittelbare Vergleichbarkeit der Resultate unter Berücksichtigung der jeweiligen Messunsicherheit ist essentiell für die Entscheidung, welche analytische Methode auf weitere archäologische Artefakte angewendet werden soll, um bei möglichst geringem Eingriff die aussagekräftigsten Informationen zu liefern. [1] J.R. Cann, C. Renfrew, Proc. Prehist. Soc. 30 (1964) 111-132. [2] R.G.V. Hancock, T. Carter, J. Archaeol. Sci. 37 (2010) 243–250. [3] G. Poupeau et al., J. Archaeol. Sci. 37 (2010) 2705-2720.

The two obsidian sources from the island of Melos (Greece), Agia Nychia and Demenegakion, are chemically characterized by three complementary analytical techniques. Ion beam analysis (IBA) comprising of particle induced X-ray emission (PIXE) and particle induced gamma-ray emission (PIGE), neutron activation analysis (NAA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are applied to the same set of geological obsidian samples. The combination of methods allows a more complete characterisation of obsidian sources and reveals a highly specific chemical composition, the so-called chemical fingerprint. This multi-methodical approach checks also the self-consistency of the analytical results and shows the most reliable and characteristic key elements Co and Sc, but also Fe, Ca and Ti of Melos obsidian deposits. NAA contributes the largest number of reliable elements to the most unambiguous chemical fingerprint comprising in total of 41 elements. Therefore, NAA is the most suitable analytical method for a clear identification of Melos obsidian deposits. Moreover, the accuracy of methods is demonstrated by the excellent correspondences (calculated correlation coefficient R2=1.00 for IBA and NAA, R2=0.99 for LA-ICP-MS) between determined analytical results obained by IBA, NAA and LA-ICP-MS and certified values of the reference glass BAM-S005B.

In 2006, Arias et al.[1] chemically characterized a new obsidian source on the island of Melos. This third obsidian source, obsidian blocks inside the volcanoclastic deposits at Agios Ioannes, was claimed to be well distinguishable from the two well-known sources Agia Nychia and Demenegakion. Following a sampling campaign in 2010, investigations of samples collected from all three Melos obsidian finding spots (Agia Nychia, Demenegakion, Agios Ioannes) were performed by three complementary analytical techniques (Neutron Activation Analysis, Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry, Ion Beam Analysis). Unfortunately, investigations had to be conducted on rubblestones, since the obsidian blocks described by Arias et al. could not be located. The “chemical fingerprint” composed of 43 elements clearly separates the rubblestones into the two known groups of Agia Nychia and Demenegakion. Elevated Sb concentrations already mentioned in Arias et al. could be confirmed but are probably attributed to a local contamination. References: [1] Arias et al., J. Radioanal. Nucl. Chem. 268 (2006) 371–386.

The natural volcanic glass obsidian is one of the classical objects of archaeometrical analyses. Reliable provenancing by means of its highly specific chemical composition, the “chemical fingerprint”, can provide information about economy, policy and the social system of ancient societies. Although Mediterranean obsidian have mainly been the focus of characterization since the pioneer work of Cann and Renfrew (1964), provenancing of Central and Eastern Europe obsidian sources attracts increasing attention in the past decades. Fingerprinting of Hungarian and Slovakian obsidian sources is of great interest especially for Central European sites where obsidian has been widely used (Williams-Thorpe et al., 1984, Kasztovszky et al., 2008, Biró, 2009). The application of three complementary analytical techniques on the same set of raw material samples allows both, a more complete characterization of obsidian sources and a comparison of analytical results. The aim of this multi-methodical approach is to apply three different analytical methods, in particular: • Instrumental Neutron Activation Analysis (INAA), • Ion Beam Analysis (IBA) comprising of Particle Induced X-ray Emission (PIXE) and Particle Induced Gamma-ray Emission (PIGE) • Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) to detect a maximum element spectrum and to compare element concentrations determined with at least two analytical techniques. This way a check of self-consistency of analytical results is possible. Furthermore, it allows the identification of a maximum of compositional differences between Hungarian and Slovakian sources by revealing the most characteristic “chemical fingerprint” composed of more than 40 elements. For this study, NAA, IBA and LA-ICP-MS measurements are scheduled to be applied to 25 raw material samples from sources from Hungary and Slovakia in cooperation with the Natural History Museum Vienna (Hammer, V. and Seemann, R., Department of Mineralogy and Petrography) and the Vienna Lithothek (Trnka, G., Department of Prehistoric and Protohistoric Archaeology). Up to now, IBA studies have already been carried out using the external 4 MeV proton beam of the 6 MV Tandem accelerator of the Ion Beam Centre of Helmholtz-Zentrum Dresden-Rossendorf. Further NAA investigations will be performed at the TRIGA Mark II 250 kW research reactor of the Atominstitut in Vienna. LA-ICP-MS measurements will be conducted using the Thermo Element 2 ICP-MS coupled to an ArF gas Excimer laser system at the Aberystwyth University. CANN, J.R. AND RENFREW, C, 1964. The characterization of obsidian and its application to the Mediterranean Region. Proceedings of the Prehistoric Society 30, 111-131. WILLIAMS-THORPE, O., WARREN, S.E. and NANDRIS, J.G., 1984. The distribution and provenance of archaeological obsidian in central and eastern Europe. Journal of Archaeological Science 11, 183-212. KASZTOVSZKY, Z., BIRÓ, K., MARKÓ, A. and DOBOSI, V., 2008. Prompt gamma activation analysis for non-destructive characterization of chipped stone tools and raw materials. Journal of Radioanalytical and Nuclear Chemistry 278, 293-298. BIRÓ, K.T., 2009. Sourcing Raw Materials for Chipped Stone Artifacts: The State-of-the-Art in Hungary and the Carpathian Basin. In: Adams, B. and Blades, B.S. (Eds.) Lithic Materials and Paleolithic Societies (eds B. Adams and B. S. Blades), Wiley & Blackwell, 47-53.

Provenancing of ancient ceramics is a highly important scientific tool for archaeological studies. In general, ceramics are not made from the original clay, as it can be found in deposits. To produce the needed physical properties in the finished product, the clay has to be either tempered by adding sands or biological materials or levigated, to remove the coarse fraction. Thus, the chemical composition of the finished ceramic differs from the composition of the original clay bed. To overcome this obfuscation, any information that can be gained about the temper used is useful. In a small series, several pieces of ceramic were produced from known clay and tempers and the resulting ceramics analysed by INAA. As many attempts to physically separate the temper from the clay matrix have failed, μ-spot analysis of temper inclusions were performed at the μ-PIXE (Particle induced X-Ray Emission) facility in Rossendorf and by LA-ICPMS (Laser ablation Inductively coupled plasma mass spectroscopy) in Aberystwyth. It could be shown that from a small number of measurements, a general impression of the temper used could be gained, showing if the temper consists mainly of quartz, feldspars or other main components. With this information, dilution calculations can be greatly facilitated, and a close resemblance of the chemical composition of the clay matrix can be calculated.

Radioactive or stable cosmogenic nuclides are products of nuclear reactions induced by cosmic rays. The development of the interdisciplinary field of the quantification of cosmogenic nuclides has been increased dramatically in the last decades. Especially, the progress in the field of accelerator mass spectrometry (AMS) improved detection limits and accuracy and allows nowadays the determination of radionuclide concentrations as low as of 104-105 atoms/(g rock). In particular, in-situ produced cosmogenic nuclides – so-called terrestrial cosmogenic nuclides (TCN) - have proved to be valuable tools for quantifying Earth's surface processes. Here, the work-horses are 10Be and 26Al in quartz, and 36Cl in Ca- or K-rich minerals. In siliceous environments both radionuclides, 10Be and 26Al, are pure high-energy spallation products, thus, the influence on the secondary neutron field by changing trace element concentrations in the original bulk matrix is negligible. Another advantage: Usually, quartz can be easily cleaned from other mineral phases making the normalization to (g SiO2)-1, i.e. only two target elements, very straightforward. There is usually no need for a full chemical analysis. In contrast, 36Cl can be produced by several different nuclear reactions: Spallation on different target elements, mainly Ca and K (to a lesser extent Ti and Fe), induced by high-energy neutrons and muons. Thus, every sample that will be analysed for TCNs has to be chemically analyzed for the main target elements, too. Additionally, as 36Cl can be produced by thermal neutron-capture on 35Cl, trace elements influencing the thermal neutron field have to be unavoidably also measured. This includes U and Th as “background”-neutron emitter, all elements with high neutron absorption cross sections like B, Gd, and Sm, and all light elements, which take part in (gamma,n)-reactions. Thus, a complete bulk rock analysis (for the neutron field) and measurements of the main target elements in the dissolved fraction are absolutely necessary. As 36Cl concentrations will be normalized to (g Ca)-1, (g K)-1 etc., the overall result cannot be more precise then the corresponding target element data. We have selected typical samples with different fractions of silicate- and calcite-rich phases to have them analyzed by the method of choice of most TCN-user: inductively coupled plasma optical emission spectrometry (ICP-OES). Unfortunately, the two French CNRS laboratories involved, CEREGE and CRPG-SARM, did not produce concordant results for all elements of interest. Thus, we have tested the capability of two non-destructive activation analysis methods: We performed Instrumental Neutron Activation Analysis (INAA) ourselves at Vienna and we sent aliquots for Prompt Gamma Activation Analysis (PGAA) to Budapest. The four laboratories performed differently depending on the analyte. For example, all methods produce CaO-data with unacceptable high uncertainties. PGAA seems to underestimate the true CaO-value of some samples. K2O-data (@ 0.1-0.7%) by ICP-OES has exceptional high uncertainties and is constantly lower as corresponding INAA- and PGAA-data. As a conclusion, it seems advisable to use more than a single analytical method, if precise TCN applications are intended.