Y. Suzuki et al., Forensic discrimination of bottle glass by refractive index measurement and analysis of trace elements with ICP-MS, ANAL SCI, 16(11), 2000, pp. 1195-1198
Measurement of refractive index and trace element analysis by ICP-MS were a
pplied to the forensic discrimination of bottle glass samples from differen
t origins. Refractive index was calculated from the matching temperature at
which glass fragments became invisible in the silicone oil. Sample solutio
n for ICP-MS was prepared by dissolving approximately 10 mg of glass fragme
nts into a mixture of 0.5 mi of KF and 0.5 mi of HClO4 and heating for 2 h
using a microwave oven, followed by dilution to 25 mi after 2 mi of HNO3 wa
s added. Thirteen elements (Co, Cu, Zn, Rb, Sr, Zr, Ag, Sn, Sb, Ba, La, Ce
and Pb) were found to be useful for the discrimination of bottle glasses. T
hese elements in NIST SRM 612 (Trace Elements in Glass) could be determined
with an RSD less than 3.2%, except for Sn and Pb. The proposed method was
applied to 16 bottle glass samples. Of 120 pairs among 16 bottle samples, 1
3 pairs were indistinguishable by RI only. Combination of trace element ana
lysis by ICP-MS and refractive index measurement made it possible to distin
guish all the pairs.