Imitation of archeological artifacts or replacing the authentic ones with fake replicates is a universal
problem / it is particularly important in Turkey for historical metal objects. Traditionally used visual
inspection methods alone are not sufficient for the solution of contemporary problems. In this study,
chemical characterization has been used to determine the differences between the authentic and fake
objects. The non-destructive analyses were carried out by Portable X-ray Fluorescence Spectrometry
(P-XRF). Silver Roman Coins (27 B.C. to 244 A.D.) were the objects handled in this research. In
particular the concentrations of Zr, Pt, Pb and Bi were used for differentiation / it has been observed
that the concentrations have different trends in the authentic and fake silver coins. In authentic coins
the average Pb concentration was found to be 0.77%, while this value was 0.055% for the fake ones.
Bi could be determined in 86% of the authentic coins while it could not be detected in any fake coin.
It has been generally observed that the silver and copper concentrations could not be utilized in
authenticity tests. Another approach was the use of Line Scanning Electron Microscopy-Energy
Dispersive X-Ray Fluorescence Spectrometry (LSEM-EDX). Using LSEM-EDX technique, it was
observed that the concentration changes near the interface between the matrix and the copper-rich
locations exhibits difference behaviors for the authentic and fake objects. This difference is originated
by the fact that a newly formed copper amalgam contains copper-rich phases while with extended
time concentration changes at interfaces become more gradual or not detectable. Pearson correlation
was used in order to elucidate the relations between the element concentrations determined by P-XRF.
In order to see whether the authentic and silver fake coins can form separate groups, dendograms have
been constructed utilizing SPSS 16.0 software and Euclidian Square Distance method. It has been
observed that the authentic and fake coins can be successfully grouped when the proper statistical
choices are used. It has been observed that these groups have significant differences using t-test. The
selected and used technology is proposed for use by museums and entities keeping archaeological
collections in order to prevent forgeries.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/12615717/index.pdf |
| Date | 01 March 2013 |
| Creators | Aydin, Mahmut |
| Contributors | Ataman, Osman Yavuz |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | Ph.D. Thesis |
| Format | text/pdf |
| Rights | Access forbidden for 1 year |
Page generated in 0.0015 seconds