<P> Seurat's palette consisted of the usual pigments of his time such as cobalt blue, emerald green and vermilion . Additionally, Seurat used then new pigment zinc yellow (zinc chromate), predominantly for yellow highlights in the sunlit grass in the middle of the painting but also in mixtures with orange and blue pigments . In the century and more since the painting's completion, the zinc yellow has darkened to brown--a color degeneration that was already showing in the painting in Seurat's lifetime . The discoloration of the originally bright yellow zinc yellow (zinc chromate) to brownish color is due to the chemical reaction of the chromate ions to orange - colored dichromate ions . In the third stage during 1888 - 89 Seurat added the colored borders to his composition . </P> <P> The results of investigation into the discoloration of this painting have been ingeniously combined with further research into natural aging of paints to digitally rejuvenate the painting . </P> <P> In 1923, Frederic Bartlett was appointed trustee of the Art Institute of Chicago . He and his second wife, Helen Birch Bartlett, loaned their collection of French Post-Impressionist and Modernist art to the museum . It was Mrs. Bartlett who had an interest in French and avant - garde artists and influenced her husband's collecting tastes . Sunday Afternoon on the Island of La Grande Jatte was purchased on the advice of the Art Institute of Chicago's curatorial staff in 1924 . </P> <P> In conceptual artist Don Celender's 1974--5 book Observation and Scholarship Examination for Art Historians, Museum Directors, Artists, Dealers and Collectors, it is claimed that the institute paid $24,000 for the work (over $328,000 in 2013 Dollars). </P>

Where is a sunday afternoon on the island of la grande jatte located