The breakthrough developments in X-ray instrumentation regarding miniaturized air-cooled X-ray sources and X-ray detectors operated in room temperature have driven and boosted the activities of the XRF laboratory towards the development of customized portable XRF spectrometers. After the first in-situ campaign at the archaeological museum of Nicosia in Cyprus, a prototype milli-beam portable XRF spectrometer was developed (2002-2003) at INPP and its overall analytical performance was carefully evaluated and optimized in the analysis of different kind of archaeological/historical materials.
Through the provision of analytical services and technology know-how, several similar pXRF spectrometers were produced and delivered to end-users, including the Stone Center of the Ministry of Culture, the Archaeological Museum of Volos, the Benaki museum, the Paleoenvironment and ancient metallic structure laboratory of INN and the University of Cyprus. In addition, with the support of Thera Foundation a semi-micro prototype XRF spectrometer was developed and characterized (2003), whereas in 2005 a state of the art, customized version of the Artax commercial micro-XRF spectrometer was acquired with the support of FP6 project PROMET (Project ID: 509126, 2004-08) “Innovative conservation approaches for the monitoring and protection of ancient and historic metal collections from the Mediterranean basin” and applied in surveying museum metals collections across the Mediterranean basin. A systematic study of the micro-XRF spectrometer characteristics was undertaken regarding the analytical description of its elemental excitation response, spatial resolution and analytical sensitivity. Optimized analysis protocols were developed towards an accurate, precise compositional analysis of metal alloys composition overcoming spectral interferences that arise due to the polycrystalline nature of the alloys surface. The micro-XRF spectrometer was evaluated in terms of its analytical performance to identify corrosion products. Artificially corroded copper and silver coupons and corresponding ancient alloys were measured exploring various experimental (single spots analysis, line or area elemental mapping) or analytical methodologies (for example the variation of the intensity ratio of two characteristic X-rays of the same elements).
The XRF laboratory spectrometers supported several in-situ campaigns at archaeological sites and museums in Greece and abroad (Ancient Aigai, Archaeological Museum of Thessaloniki/Nafplion/Thebes/Chora-Pylos Messenias/Olympia/Kalymnos/Ancient Messene/Delos/Poros, the National Archaeological Museum of Athens, the Akrotiri site in Thera island, the Phaistos site in Crete, the Armoury museum in Malta, the National Archaeological Museum of Damascus, Syria and the Numismatic museum of Yarmouk University in Jordan These investigations were accomplished in close cooperation with colleagues from foreign archaeological schools in Greece (American, Italian, French, Swedish, German), Greek and Foreign research and academic institutions.