Problems of Forensic Sciences 2001 Vol. 47 (XLVII) 80-92
THE DIFFERENTIATION OF FLOAT GLASS USING REFRACTIVE INDEX AND ELEMENTAL ANALYSIS: COMPARISONS OF TECHNIQUES
Stefan BECKER1, Lawrence GUNARATNAM2, Tacha HICKS3, Wilfried STOECKLEIN1, Geoff WARMAN4
1Bundeskriminalamt, Forensic Science Institute, Wiesbaden, Germany
2National Bureau of Investigation, Crime Laboratory, Vantaa, Finland
3Institut de Police Scientifique et de Criminologie, Lausanne, Switzerland
4Metropolitan Laboratory, Forensic Science Service, London, United Kingdom
Streszczenie
In order to evaluate differences between the results of elemental analysis of glass a proficiency test was carried out during the period 1999/2000. The initial work on this project was presented at the first EAFS Meeting in Lausanne in 1997. Three pairs of glass samples with similar refractive indices had to be examined using refractive index measurements and elemental analysis. In this study SEM-EDX, μXRF, and ICP/MS were used for the elemental analysis. Based on the refractive index measurements a complete differentiation of the glasses was not possible. Annealing of the glass enabled further differentiation. After the use of the elemental techniques a full differentiation of the six glasses was possible. The strategies used by different laboratories in order to discriminate between the samples and the merits of the various techniques applied are discussed.
Słowa kluczowe
Annealing; Float glass; Forensic glass analysis; ICP/MS; Proficiency test; SEM-EDX; μXRF.