Non-destructive testing of metal archaeological relics on the example of zinc dog tags discovered during the exhumation of people murdered in the Remand Prison at 37 Rakowiecka Street in Warsaw

Abstract

The paper presents investigations of two partially damaged military dog tags. One of them is in relatively good condition while the second one is strongly damaged. Investigations focused on the better preserved military dog tag. Some of the characters were illegible. Thus the aim of the investigations was to identify the originally stamped characters using the multispectral method. The idea was to investigate objects not only in the visible part of the electromagnetic spectrum but also in other ranges, such as the near-infrared or the long-wave infrared spectral range. The research made use of dynamic infrared thermography, near-infrared techniques (with additional excitation by a near-infrared source) and visible techniques.