Examination of Firearms Review: 2007 to 2010 - Interpol

Natural versus artificial ultramarine blue pigments were differentiated by the
presence of calcite in the former using LIBS, pulsed Raman spectroscopy,
principal components analysis, and light microscopy in another paper by Osticioli,
et al. [298] Several other combined LIBS and Raman studies were also carried
out that demonstrated the efficiency of and complementary information resulting
from the use of the techniques both in a single instrument setup [299-301] and as
stand-alone technique.[302]
21. Laser ablation inductively coupled plasma – mass spectrometry (LA-
ICP-MS)
LA-ICP-MS was reviewed by Giussani and coworkers in which the main issues
relating to cultural heritage are discussed, followed by a description of the
features, advantages, and drawbacks of LA-ICP-MS. Pigments are briefly
mentioned.[303]
LA-ICP-MS was combined with SEM/EDS and Raman by Resano et al. to
characterize pigments in rock art. LA provided the most relevant data for
associating samples and was capable of providing spatially resolved (both
laterally and in depth) quantitative multielement information for elements present
in a wide concentration range.[304]
Arnold and coauthors used LA-ICP-MS for sourcing of materials and compared
the results to instrumental neutron activation analysis (INAA). Similar data was
obtained but LA-ICP-MS was preferred due to its ease, smaller analytical
investment, and near non-destructiveness. LA also determined some elements
that INAA could not.[305]
22. Gas Chromatography
GC was used in combination with different sample preparation techniques and
detectors for the analysis of various organic components used in cultural
heritage.
Derivatizing reagents and GC/MS were used by Caruso et al. for the analysis of
the varnish (fatty acids) and the glue (proteinaceous amino acids) on a musical
instrument and also by Echard and coauthors for the analysis of varnishes on
three ancient musical instruments.[306;307] For a general review of the
characterization of varnishes on musical instruments, refer to [286]. Edwards
and coauthors used Raman spectroscopy to pinpoint areas for GC/MS analysis
of varnishes on ancient Egyptian sarcophagal fragments, while Singer and
McGuigan used GC/MS to analyze fatty acids, amino acids, and natural resins in
paints.[308;309] Gautier and Colombini attempted to determine the
proteinaceous binder composition in wall paintings by purifying proteins through
the removal of inorganic salts that impair the determination of the protein via
amino acid analysis.[310]
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