Aula Leopoldina is the most representative, baroque hall in Wroclaw University. In 2008, LIBS measurements of
paintings layers of Aula vault were done. LIBS spectra permitted identification of mineral pigments used for specific
colors of painting layers. This identification could not be unambiguous in each case since simultaneous occurrence of
elements that could be components of different pigments of the same color was observed in some samples. For example,
in some red samples the presence of aluminum and iron was stated, and hence red ochre or Mars red could be used as a
pigment. In other samples the cinnabar can be additionally responsible for red color. Similar problems were observed in
case of blue pigments, where existence of copper may show that azurite was used, but the presence of aluminum,
sodium, silicon and iron can point to application of ultramarine, Egyptian or Prussian blues. The greatest difficulties
occurred during identification of white pigments. Because of presence of barium, zinc, lead and titanium, the potential
pigments might be lithopone, barite, zinc white, lead white or titanium white. Final choice of the pigment is determined
by the time of last renovation and this points out that the zinc white was used.
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