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:John Bennett, Mitsuru Ebihara, Tsuyoshi Tanaka, Paul Armishaw, Raluca Iavetz, Vu Cao, Syed Hossain, Donghui Huang, Sutisna, and Nazaratul Salim
Eight neutron activation analysis research groups from seven countries have participated in a trial proficiency test under
the auspices of the Forum for Nuclear Cooperation in Asia. Three stream sediment reference materials were used in the test.
A high degree of proficiency was found in the quantification of Co and Sc and more than 20 elements were well quantified by
the majority of laboratories. The results support the use of neutron activation analysis, as practised by the participants,
for geochemical mapping. The data produced in this study may provide an opportunity to improve the characterisation of the
three reference materials.
Authors:Rachel Popelka-Filcoff, Claire Lenehan, Michael Glascock, John Bennett, Attila Stopic, Jamie Quinton, Allan Pring, and Keryn Walshe
Ochre is a significant material in Aboriginal Australian cultural expression from ceremonial uses to its application on many
types of artifacts. However, ochre is a complex material, with associated surrounding minerals potentially challenging the
overall analysis. In recent literature several studies have attempted to characterize ochre by a variety of techniques to
understand procurement and trade. However, ochre is difficult to differentiate on major elemental or mineralogical composition
and requires a detailed analysis of its geochemical “fingerprint”. Neutron activation analysis (NAA) provides the high sensitivity
(sub-ppm), precision and accuracy in multi-elemental analysis required for ochre. The elements of interest for ochre generally
include rare earth elements (REEs) and certain transition metal elements as well as arsenic and antimony. Data from relative
comparator NAA (MURR, University of Missouri, USA) is compared with data from k0-NAA OPAL (ANSTO, Lucas Heights, Australia). A discussion of the two methods will be examined for their utility in “fingerprinting”
the provenance of ochre. The continuing importance of NAA to archaeometry will also be discussed.