We report on a study of ultramarine pigments via Colorimetry, resonance Raman, and ~(27)Al, ~(29)Si solid-state NMR spectroscopy. NMR parameters are shown to correlate well with the intensities of Raman signals corresponding to the chromophores S_3~(-·) and S_2~(-·) . Further, a correlation is established between the colorimetric parameters L~* (lightness) and C~* (chromaticity) and the paramagnetic shift in NMR spectra for both ~(27)Al and ~(29)Si. The parameter h (hue) appeared not to vary over the range of paramagnetic host concentrations studied. Preliminary results on faded pigments in both acidic and basic media show that the concentration of diamagnetic guest molecules in the sodalite lattice rises, and some of the paramagnetic species are replaced.
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