NCJ Number
172048
Journal
Journal of Forensic Sciences Volume: 42 Issue: 3 Dated: (May 1997) Pages: 424-428
Date Published
1997
Length
5 pages
Annotation
This article presents the instrumentation and results of an experiment that used qualitative X-ray microfluorescence analyses to interpret various types of gunshot residues around bullet entry wounds.
Abstract
The results were obtained with a Kevex Omicron energy dispersive X-ray microfluorescence spectrometer equipped with a Rhodium anode microfocus X-ray tube. All the analytical results were obtained by using maximum operating tube voltage (50 kV) and various amperage levels to optimize data throughput. The results presented in this paper were achieved by using a 300 micron final beam collimator. The residues to be detected were lead (Pb), antimony (Sb), barium (Ba), copper (Cu), zinc (Zn), and iron (Fe). Pb comes from the bullet, the primer, and also from some small previous deposit in the gun barrel. Sb comes from the bullet and/or from the primer. Ba comes from the primer only, and Cu and Zn usually come from the metal jacket of the bullet; Fe usually comes from the barrel of the gun. When possible, the bullet extracted from the fatal gunshot wound or an identical one can be analyzed to determine whether Sb has been added to Pb in the bullet itself. When entry wounds are made from a firearm discharge at contact or point blank range, residue results will typically include all of the above elements. When wounds are inflicted by a firearm at greater distances, fewer of the elements will be found. This paper shows the likely composition of the firearm residue around a gunshot wound as firing distances increase. 4 figures, 4 tables, and 8 references