The XR-100CR fitted with a 109Cd Annular source performing XRF on a painting.
The XRF spectrum of the painting.
Photo and spectrum provided courtesy of Zoltán Szõkefalvi-Nagy.
Z. Szõkefalvi-Nagy, A. Kocsonya, I. Demeter and I. KovácsOn the XRF detection of Ti in white spots of paintings, Proc. of art2002, the 7th Int. Conf. on Non-destructive Testing and Microanalysis for the Diagnosis and Conservation of the Cultural and Environmental Heritage:, 2-6 June 2002, Antwerp, Belgium (Eds. R.Van Grieken, K.Janssens, L. Van’t dack and G. Meersman), pp. 327 – 335.
Z. Szõkefalvi-Nagy, I. Demeter, A.Kocsonya, I. Kovács, “Non-destructive XRF analysis of paintings,” Nuclear Instruments and Methods B 226 (2004), 53-59.
Mapping sulphates on Michelangelo’s David using portable EDXRF (from “Exploring David: diagnostic tests and state of conservation,” edited by S. Bracci et al., GIUNTI, Florence, 2004)
Giovanni Buccolieri, Alfredo Castellano, Marina Donativi, Stefano Quarta
Universita di Lecce, Dipartimento di Scienza dei Materiali
At the request and invitation of the Thera Foundation a group from Amptek Inc. and Photoelectron Corp. journeyed to Thera to analyze a gold ibex that was recently found at Akrotiri. The analysis was performed using x-ray fluorescence techniques (XRF). Other artifacts were also analyzed, ranging from pottery to wall paintings and daggers. The x-ray detector used was the Amptek XR-100CR and the x-ray source was the Photoelectron XRS tube.
The gold ibex was perhaps the most unique object analyzed in that it is the only artifact made of precious metals found at Akrotiri. All other precious objects were removed from the site by Thera inhabitants before the eruption that devastated the island and buried the settlement beneath meters of ash. It is also of note because it comes from an important public building (conventionally called the “building of the benches”), which was in close proximity to the famous Xeste 3 building where the rituals for the young boys and girls of the local elite class took place. The fact that the ibex was found in-situ makes its importance even greater since this object is stylistically unique and it could be considered even as fake in the international art market.
Here is Prof. Doumas’ description from the relevant chapter of the catalogue of the new museum:
“Unexpected among the many and wealthy finds of the excavations made for the foundations of the pillars of the new shelter, is the gold figurine found on December 1999. Unique of its kind, it was discovered in mint condition, inside a wooden box (only the imprint has survived) inside a clay chest (larnax), next to a large pile of horns, mainly of goats. Excavation of the find-spot is still in progress and it is therefore too early to draw conclusions about the figurine’s significance (I would say that it was offered as a gift from someone coming from the East or that it is a sacrificial object related to worship or other rituals). The figure is hollow and was cast by the “lost wax” method. The legs, neck, and tail of the animal were soldered on after the removal of the inside core. In the finishing process the figure was hammered, as deduced from the tool-marks.”
Below is a comparison of two spectra taken from the Gold Ibex. The Goat_1 spectrum was taken from just above the front left leg. This position is free of visual contaminants and considered to be the base spectrum. The Goat_4 spectrum is from the braze/weld of the tail. It shows an increase in the amount of Copper (Cu).
Below are pictures of some of the other artifacts analyzed.
T. Pantazis, A.G. Karydas, Chr. Doumas, A. Vlachopoulos, P. Nomikos, M. Dinsmore, “X-Ray Fluorescence Analysis of a Gold Ibex and other Artifacts from Akrotiri,” Presented at the 9th International Aegean Conference: Metron, Measuring the Aegean Bronze Age at Yale University, April 18-21, 2002. Published in Aegaeum 24 (2003).
The XR-100CR is shown above performing X-Ray fluorescence of Benvenuto Cellini’s Bronze statue of Perseus during its restoration in June, 1998 at the Uffizi Museum in Florence.
Example of a spectrum of the Perseus right knee showing that the bronze alloy is composed by copper, tin (~3.6%), lead (~6%), antimony (~1%), iron (<1%) and silver (<1%). The composition of the alloy slightly changes in other points of the statue. The x ray tube is equipped with a W-anode and the HV is 35 KV.
Example of the influence of a green patina on the detected spectrum. It is easy to see that the photons generated in tin atoms (corresponding to the peak at 25.2 keV) penetrate easily through the patina while the copper and lead ones are strongly absorbed. In this way, you can check the status of the patina and verify its composition.
Reproductions regarding the XRF analysis campaign in collaboration with the University of Sassari, the University of Roma and Lecce and with the Central Institute for Restoration of Roma.
Analysis of a bronze statue from Messina, Italy c.16th century.
|Above is the X-Ray Instrument used for the analysis. Inside the instrument are the XR-100CR and the X-Ray tube. Below is a close-up of the statue indicating the points where the spectra were taken.|
The Amptek XR-100T-CZT Detector is shown performing x-ray fluorescence and x-ray diffraction analysis on an ancient Etruscan vase (note that the XR-100T-CZT has been replaced with the XR-100T-CdTe). The portable instrument, which includes the CZT Detector, an x-ray tube and the Amptek MCA-8000 Multichannel Analyzer for data analysis, enables examination of art objects in museums and archeological sites.
The instrument, developed by the National Council of Research in Italy and commercialized by ASSING S.p.A., was described in a paper presented at the TMS Annual Meeting in San Antonio, TX in February 1998. SEXI (Structural & Elemental X-Ray Instrument) is a multifunctional instrument for in-situ, non-destructive, real-time analysis of chemicals, minerals and texture.
Above: The XR-100T-CZT performing in-situ nondestructive X-Ray fluorescence analysis on the “Portland” vase from Pompeii at the National Museum of Naples, Italy.
It is estimated that over 100 publications in the art and archaeology world have utilized Amptek detectors. This estimate was performed by searching for the use of Amptek detectors in the Scientific Journals: IEEE Trans Nucl Sci, Nucl Instrum Methods Phys Res A, Nucl Instrum Methods Phys Res B, Adv X-Ray Anal, Aegaeum, X-Ray Spectrometry, Spectroscopy, and the book X-Rays For Art and Archaeology.
X-Ray Spectrometry, Special Issue: Art and Cultural Heritage Research, July/Aug 2008, Vol 37 No. 4, p. 285-474, ISSN 0049-8246.
Studies in Archaeological Sciences: Handheld XRF for Art and Archaeology. A. N Shugar & J. L. Mass (eds.), Leuven University Press, 2012.
T. Pantazis, A. G. Karydas, Chr. Doumas, A. Vlachopoulos, P. Nomikos, M. Dinsmore, “X-Ray Fluorescence Analysis of a Gold Ibex and other Artifacts from Akrotiri,” Aegaeum 24: METRON, Measuring the Aegean Bronze Age, 2003.
M. Uda, G. Demortier, I. Nakai, X-Rays for Archaeology, The Netherlands: Springer, 2005.
A.G. Karydas, X. Brecoulaki, T. Pantazis, E. Aloupi, V. Argyropoulos, D. Kotzamani, R. Bernard, Ch. Zarkadas, Th. Paradellis, “Importance of in-situ EDXRF Measurements in the Preservation and Conservation of Material Culture,” X-Rays for Art and Archaeology, M. Uda et al. (eds.), 27-53, 2005.
M. Uda, “Characterization of Pigments Used in Ancient Egypt,” X-Rays for Art and Archaeology, M. Uda et al. (eds.), 3-26, 2005.
Cesareo, R., G.E. Gigante, A. Castellano, “Thermoelectrically cooled semiconductor detects for non-destructive analysis of works of art by means of energy dispersive X-ray fluorescence,” Nucl. Instr. and Meth., A428, pp. 171-181, 1999.
Cesareo, R., A. Brunetti, “X-ray fluorescence – analysis of 19th century stamps”, X-ray Spectrometry 37, pp 260-264 (2008).
Roberto Cesareo, Antonio Brunetti, Stefano Ridolfi, “Pigment layers and precious metal sheets by energy-dispersive x-ray fluorescence analysis,” X-Ray Spectrometry 37, 309-316, 2008.
Janssens,K., G. Vittiglio, I. Deraedt, A. Aerts, B. Vekemans, L. Vincze, F. Wei, I. Deryck, O. Schalm, F. Adams, A. Rindby, A. Kn¨ochel, A. Simionovici and A. Snigirev, “Use of Microscopic XRF for Non-destructive Analysis in Art and Archaeometry”, X-Ray Spectrometry 29, 73-91, 2000.
Aceto Maurizio, Angelo Agostino, Enrico Boccaleri, Anna Cerutti Garlanda, “The Vercelli Gospels laid open: an invenstigation into the inks used to write the oldest Gospels in Latin,” X-Ray Spectrometry 37, pp 286-292 (2008).
M. Gil, M.L. Carvalho, A. Seruya, I. Ribeiro, P. Alves, A. Guilherme, A. Cavaco, J. Mirao, A. Candeias, “Pigment characterization and state of conservation of an 18th centrury fresco in the Convent of S. Antonio dos Capuchos (Estremoz),” X-Ray Spectrometry 37, 328-337, 2008.
L. Pappalardo, G. Pappalardo, F. Amorini, M.G. Branciforti, F.P. Romano, J.de Sanoit, F. Rizzo, E. Scafiri, A. Taormina, G. Gatto Rotondo, “The complementary use of PIXE-a and XRD non-destructiver portable systems for the quantitative analysis of painted surfaces,” X-Ray Spectrometry 37, 370-375, 2008.
A. Guilherme, A. Cavaco, S. Pessanha, M. Costa, M.L. Carvalho, “Comparison of portable and stationary x-ray fluorescence spectrometersin the study of ancient metallic artefacts,” X-Ray Spectrometry 37, 444-449, 2008.
Mapping sulphates on Michelangelo’s David using portable EDXRF (from “Exploring David: diagnostic tests and state of conservation,” edited by S. Bracci et al., GIUNTI, Florence, 2004), Giovanni Buccolieri, Alfredo Castellano, Marina Donativi, Stefano Quarta, Universita di Lecce, Dipartimento di Scienza dei Materiali.Need More Information?