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Abstract  

The k 0-method of standardisation for instrumental neutron activation analysis (INAA) has been used at the OPAL research reactor to determine the elemental composition of three certified reference materials: coal fly ash (SRM 1633b), brick clay (SRM 679) and Montana soil (SRM 2711). Of the 41 certified elements in the three materials, 88 percent were within five percent of the certified values and all determinations were within 15 percent of the certified values. The average difference between the measured and certified values was 0.1 percent, with a standard deviation of 4.1 percent. Since these reference materials are widely used as standards in the analysis of archaeological ceramics by INAA, it has been concluded that the INAA facility in Australia is particularly well-suited for nuclear archaeometry.

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Abstract  

Chemical and mineralogical analysis was performed on ceramics and clay samples from Barracão archaeological site located in Baixo São Francisco River by means of instrumental neutron activation analysis (INAA) and by differential scanning calorimetry (DSC). The data set was studied by means of cluster analysis (CA) and discriminant analysis (DA). The results showed that the raw material used in ceramics is not local. By using DSC it was possible to discover that the principal minerals in the samples are quartz, feldspars, mica and kaolinite.

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Abstract  

PIXE analysis method is applied to archaeometry problems. Advantages and disadvantages are emphasized. Some examples are presented which show the difficulties; especially important heterogeneities of ceramics, old coins and metals restrain from the use of this technique: other analysis systems, less expensive, like electron microprobe or X-ray fluorescence spectrometry, are compared with conventional PIXE method. The importance of proton microprobe is explained.

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Journal of Thermal Analysis and Calorimetry
Authors: Rodica Mariana Ion, Irina Dumitriu, Radu Claudiu Fierascu, Mihaela-Lucia Ion, Simona Florentina Pop, Constantin Radovici, Raluca Ioana Bunghez, and V. I. R. Niculescu

ancient Pozzolanic concretes . Archaeometry . 2003 ; 43 : 4 447 – 453 . 10.1111/1475-4754.00027 . 12. Fierascu , RC , Dumitriu , I , Ion , ML , Catangiu , A , Ion , RM . Surface

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Abstract  

A collaborative program between Archaeology and Nuclear Science and Engineering (NS&E) at Cornell University has been established. Neutron activation analysis using the 500 kW TRIGA reactor at NS&E is used to analyze Etruscan pottery samples from the excavations at La Piana, near Siena, Italy. This is a progress report for the Etruscan project, and preliminary results from the statistical analysis of the data are presented.

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Abstract  

A new instrumental epithermal neutron activation analysis procedure to quantitatively determine titanium, barium, and bromine in obsidian with improved sensitivity has been developed. The advantage of epithermal activation for Ti, Ba, and Br is demonstrated with multiple geological standards and the ability to determine arsenic in obsidian is demonstrated. The results for titanium are compared to previous electron-microprobe results for Kenyan obsidian.

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Abstract  

This paper describes experimental results through multivariate statistical methods that might reveal outliers that are rarely taken into account by analysts. The results were submitted to three procedures to detect outliers: Mahalanobis distance, MD, cluster analysis, CA, and principal component analysis, PCA. The results showed that although CA is one of the procedures most often used to identify outliers, it can fail by not showing the samples that are easily identified as outliers by other methods, like MD. Mahalanobis distance proved to be the simpler application, with sensitive procedures to identify outliers in multivariate datasets.

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Abstract  

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 is 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 is useful. In a small series, several pieces of ceramic were produced from known clay and tempers and the resulting ceramics analysed by neutron activation analysis (NAA). As many attempts to physically separate the temper from the clay matrix have failed, μ-spot analysis of temper inclusions was performed at the microbeam particle induced X-ray Emission (μ-PIXE) facility in Rossendorf and with laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) at the Aberystwyth University in Wales. It could be shown that from a small number of measurements, a general impression of the temper used could be gained. Furthermore the μ-spot methods and the bulk data gained from INAA are highly comparable, extending the set of elements that can be measured. With this information, the influence of the temper on the bulk composition of the finished product can be estimated, which potentially adds crucial information to subsequent dilution calculations.

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