NON‐DESTRUCTIVE INVESTIGATION OF BRONZE ARTEFACTS FROM THE MARCHES NATIONAL MUSEUM OF ARCHAEOLOGY USING NEUTRON DIFFRACTION*

Non‐destructive neutron diffraction techniques were applied to determine composition and microstructure data, and hence to derive information on manufacturing techniques of Picenum bronze artefacts. Furthermore, texture analyses were carried out on standards and suitable ancient artefacts to investigate their potential role in archaeometallurgical studies. This is a first step towards an overall characterization of the bronze collection of the Marches National Museum of Archaeology, Italy, and the analytical demonstration of relations with and differences compared to Etruscan metallurgy. The work is also an example application of the powerful non‐destructive archaeometrical approaches provided by time‐of‐flight neutron diffraction.     

INVESTIGATION OF THE CONTENT OF ANCIENT TIBETAN METALLIC BUDDHA STATUES BY MEANS OF NEUTRON IMAGING METHODS

Many important cultural and religious objects from Asia consist of outer metallic shapes, usually bronze, which fully enclose inner contents made of organic materials such as wood, bark, paper, textile, plants and others. Bronze and other metallic materials, such as copper and silver, are generally more transparent to neutrons than to X‐rays. However, organic materials are less transparent to neutrons than to X‐rays and therefore organic materials, enclosed by metallic materials, can be made visible with neutrons. Therefore, neutron imaging (radiography and tomography) was found to be an ideal tool for the inspection of objects that consist of metal outside and organic materials inside. This has been successfully demonstrated here with four metallic Tibetan Buddha statues, providing archaeometry with a powerful new tool. The first successful applications of this novel technique are described in this article. Further possible and useful applications of neutron imaging of cultural objects are outlined.     

NEUTRON RESONANCE CAPTURE ANALYSIS OF SOME GENUINE AND FAKE ETRUSCAN COPPER ALLOY STATUETTES*

The probability of nuclei capturing neutrons reveals sharp peaks, so‐called ‘resonances’, which occur at neutron energies that are specific for each element. These resonances are very suitable for analysing the elemental composition of objects. They are the basis of a new analytical method, ‘neutron resonance capture analysis’ (NRCA). This is a fully non‐destructive method, which is applicable to almost all stable isotopes, determines the bulk elemental composition, does not require any sample preparation and results in a negligible residual activity. Recently, NRCA has been applied in a study of a series of bronze statuettes, obtained from the National Museum of Antiquity in Leiden (NL).