Examination of Firearms Review: 2007 to 2010 - Interpol

found Raman effective at establishing one artist’s palette.[213] Acquaviva, et al.
utilized Raman as well as excimer laser techniques in order to study yellow
pigments in egg yolk tempura.[214] Colomban also used Raman scattering to
study colors produced on pottery and glass using metal nanoparticles.[215]
Vandenabeele and coauthors compared the performance of five mobile Raman
instruments through evaluation of spectral resolution, wavelength calibration, and
the ability to focus through a varnish layer. The study has the potential to
facilitate a better definition of the requirements for the design of a future mobile
instrument.[216] Articles were also published that discussed case studies of
Raman spectroscopy to answer questions about specific works of art (Hernanz
2008, Baraldi 2009).[217;218]
Both organic and inorganic pigments used in pre-mixed architectural paints from
the first half of the twentieth century were discussed by Gautier, et al. with
respect to their dual use by artists such as Picasso. Raman, XRF, and FTIR
were used to analyze Ripolin ® , a commercially available brand of architectural
paints which were manufactured in Europe in the late nineteenth century for
architectural and marine applications. A major finding in this study was observed
with Raman and confirmed by PLM, in that carbon black as opposed to ivory or
bone black was used in the black Ripolin ® paint. Other findings included the
observation that lead carbonate, as well as common pigments such as vermilion,
cadmium red or yellow, emerald green, or cobalt violets, were not present in the
Ripolin ® paint, whereas it is common in tubes of traditional artists’ paints. Lastly,
the authors reported that these architectural paint formulations always create
secondary and tertiary colors from combinations of primary colors rather than the
addition of other mediums to achieve the desired effect.[219]
Perez-Pueyo and coworkers in Spain described the issues encountered in
Raman spectral interpretation due to the presence of intense fluorescence
background signals. They proposed a morphology-based automated baseline
correction and applied the concept to the analysis of artistic pigments. The
authors concluded that this approach successfully removed fluorescence-related
interferences while retaining the line shapes and positions of the Raman bands
of interest.[220]
In a separate study, Perez-Pueyo and coworkers identified artistic pigments
using a fuzzy approach as applied to data acquired via Raman spectroscopy.
The authors describe fuzzy logic as “a mathematical technique that follows the
guidelines of the human reasoning mechanism for decision making with its ability
to work from approximate data and find precise solutions.”[221]
16. Fluorescence Spectroscopy
Confocal microfluorescence spectroscopy was used by Claro et al. for the
analysis of red lake pigments in binding media, and a database was
developed.[222] The technique was subsequently applied to artwork
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