Isotope excited energy dispersive X-ray fluorescence (EDXRF) was used for the determination of the major components, silver and copper, of ancient coins. A ring shaped 125I source was used for excitation. Various methods were developed and compared for quantitative evaluation in order to eliminate matrix effects and the effects caused by the differences in geometry. The method proposed by the authors ensures determination with acceptable error using certified standard samples of alloys. The results of this method were compared with those of prompt gamma activation analysis (PGAA) and with data from contemporary written sources.
Since 1996 several applications of prompt gamma activation analysis have been performed at the new Budapest PGAA facility. This paper deals with the investigation of metal objects. We report the results of nondestructive detection of H in amorphous metals, multielement analysis of Roman bronze brooches and measurement of silver concentration in Hungarian coins.
The prompt -activation analysis (PGAA) facility at Budapest Research Reactor offers a unique possibility to perform in-beam measurements. Several k0 factors for decay -lines of short-lived nuclides have been determined accurately by means of in-beam activation. The present values compare well with literature data. New k0 factors are proposed for 24mNa and 60mCo.
Boron and chlorine concentrations in geological standards and in representative volcanic rock samples were determined by prompt gamma activation analysis (PGAA). The results of the GSJ standard measurements proved the high precision of PGAA in measuring the boron, chlorine, other trace elements (Sc, Nd, Sm, and Gd) and the major element contents of the samples. The rock samples originate from the western part of the Northern-Pannonian Volcanic Field (NPVF), which includes the Central Slovakian Volcanic Field (CSVF), the Börzsöny and the Visegrád Mts. (VMt.). The oldest 16-13.5 Ma samples as the first products of the Miocene calc-alkaline volcanism are the most enriched in B (11-29 µg/g), whereas the primitive basaltic andesites (from CSVF), the latest products (9 Ma) of the volcanic activity have lower B content (8-9 µg/g). The measured B concentrations correlate positively with fluid-mobile elements, and the trace element pattern of the samples show subduction related signatures. The chlorine content of the investigated samples shows wide variation between 42.62 and 1148.45 µg/g. The 9 Ma samples from the CSVF show Cl contents between 150-160 µg/g. In agreement with the latest geodynamic models of the Neogene calc-alkaline volcanism1,2 in the NPVF during the shallow, prograding subduction, the fluid-mobile elements metasomatized the mantle wedge. Thus the oldest volcanic rocks have relatively higher B (>11 µg/g) and high but variable Cl contents. As the subduction waned and extension proceeded, the magma generation region changed to a not thoroughly metasomatized mantle by the former subduction event, resulting in lower B, low and stable Cl content of the younger (9 Ma) volcanic rocks.
Prompt gamma activation analysis is a highly powerful analytical method in geology, due to its applicability to determine
the concentration of all major and few trace elements in whole rock samples. Furthermore, the boron concentration can be determined
with proper accuracy without time consuming sample preparation. The reliability of this method was checked on geological standards
and on other volcanic rocks, which were analyzed previously by XRF and TIMS for many major and trace element components and
Sr-isotopes. Boron concentrations of volcanic rock samples from the East Carpathian Volcanic Field (Eastern-Central Europe)
are reported here for the first time. The boron concentrations were measured for an improved definition of the petrogenezis
of these rocks and to understand the fluid addition processes during subduction-related volcanism in this region.
A major obstacle to the use of the prompt gamma activation analysis (PGAA) method has so far been the lack of a suitable library. Therefore, new measurements have been performed at the PGAA facility at Budapest Research Reactor (BRR) in order to create a prompt -ray catalog for qualitative and quantitative analysis. Prompt -ray energies and associated k0-factors have been determined by internal standardization. The resulting catalog contains prompt -ray data from neutron capture and other reactions such as (n,), and decay -ray data from short-lived reaction products. Data have been measured for nearly all stable elements, from hydrogen to uranium. Generally, data for several isotopes are given, to enable isotopic analysis as well.
New measurements have been performed at the PGAA facility at the Budapest Research Reactor (BRR) in order to create a prompt -ray catalog for qualitative and quantitative analysis. The measured spectra were accurately analyzed by HYPERMET-PC. Prompt -ray energies and associated -ray production cross-sections have been determined by internal standardization. The resulting catalog contains prompt -ray data from neutron capture and other reactions such as (n,), and decay -ray data from short-lived reaction products. Data have been measured for nearly all stable elements, from hydrogen to uranium. Generally, data for several isotopes are given, to enable isotopic analysis as well. The whole library, including elemental spectra, will be available as a book.
Recently, several archaeometrical projects were started on the prehistoric collection of the Hungarian National Museum. Among
the analytical methods applied, non-destructive prompt gamma activation analysis (PGAA) has a special importance. Based on
major-and trace components, characterization of stone tools and their raw materials were performed. Until now, 160 pieces
from Carpathian Basin and from the surrounding area (Romania, Croatia, Ukraine, Poland and the Mediterranean region) have
been analyzed, including both archaeological and geological pieces. Obsidian and Szeletian felsitic porphyry objects adequately
separable with PGAA. Identification of high silica silex categories, however, is much more difficult.
High-pressure metamorphic rocks showing a large range of chemical compositions were analyzed by PGNAA, XRF and solution ICP-MS for major components and a variety of trace elements. The large data set allowed a comparison of results from PGNAA to the established methods and revealed good agreement for most major elements and for Sc and Gd. For V, Cr, Co and Ni, PGNAA data are satisfactory only at high concentration levels. B, Cl and H were analyzed by PGNAA with very good precision, even at low concentrations.