DIFFERENT FIELDS OF APPLICATIONS - Total-Reflection X-Ray Fluorescence Analysis and Related Methods - page 360

In general, the use of most pigments is known in chronological
order [204,205] so that an approximate dating of artifacts or restored parts
of a painting is made possible. On the condition that a pigment on the painting
appeared after a certain time ( postquem ) and another one disappeared before
that time ( antequem ), a rough dating is obvious. Another way to detect
forgeries was demonstrated by the examination of a picture allegedly painted
by Modigliani (1884-1920). It showed pigments that do not correspond with the
well-known palette of this artist. In particular, the pigments emerald green and
cerulean blue appeared in the spectra of this picture while cadmium yellow and
zinc white were absent. Consequently, the painting was strongly suspected of
being a forgery [203].
Vázquez etal . combined TXRF with Fourier transform IR (FT-IR) and gas
chromatography mass spectrometry (GC-MS) for the investigation of rock art
samples at an archaeological site near the town of Susques, Argentina [206].
Inorganic and organic pigments could be identified. Manganese and iron were
detected by TXRF as oxides of a black pigment. FT-IR showed the presence of
lipids, while GC-MS identified fatty acids pointing to an animal source.
Several iconographic illuminations were also investigated by TXRF after
Q-tip sampling. It was confirmed that at least three artists are responsible for
the illumination of the“Breviarium Mayer van den Bergh”(about 1510,
Antwerp). An example is demonstrated in Figure 5.24 [203,207]. By a
characterization of specific pigment mixtures it could be confirmed that
Figure5.24. Two illuminations in the Flemish breviarium“Mayer van den Bergh”: (a) f ° 536v,
Birth of Blessed Virgin Mary; (b) f ° 552v, St. Michael. TXRF analyses of three different pigment
mixtures (1-3) corroborated the hypothesis that both pictures had been produced by the same artist
Jan Provoost. (1) light-green = azurite, white lead, and lead-tin yellow type I; (2) violet = azurite
and vermilion; (3) dark green = organic paint with the same contamination (Ca, Cu, Zn, and As) in
both figures. Figure from Ref. [203], reproduced with permission. Copyright2000, John Wiley
and Sons.