Elemental analysis by energy dispersive x-ray: a significant factor in the forensic analysis of glass

Eighty-one glass samples were analyzed by EDX; two were indistinguishable. However, when the physical properties of the glass samples were considered, all glass samples were distinguishable from each other. The need to examine glass with respect not only to physical properties but also to elemental composition has been demonstrated. The authors believe that if glass is examined only by density and refractive indexes it is quite possible to conclude incorrectly that glass samples with the same physical qualities could have originated from the same source. To confirm that the glass specimens may have in fact originated from the same source their elemental compositions in addition to density and refractive indexes must be determined. The analysis by EDX of glass samples can selectively eliminate most specimens on the basis of elemental differences. If this step is performed prior to refractive index or density measurements considerable time savings can be realized in casework situations.