Authors:John Bennett, Peter Grave, and Attila Stopic
The k0-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.
Authors:J. Santos, C. Munita, R. Toyota, C. Vergne, R. Silva, and P. Oliveira
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.
Authors:I. Brissaud, G. Lagarde, A. Sabir, and A. Houdayer
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.
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.
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.
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.
Authors:Johannes Sterba, Frans Munnik, and Nick Pearce
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