During conservation of the painted ceiling decoration of Lin'xi Pavilion in the Forbidden City, two distinct paint campaigns were isolated as a unique case study into architectural paint materials during both the Ming and Qing dynasties. Paint samples and cross sections from both paint generations were analyzed with SEM-EDX, time of flight-secondary ion mass spectrometry (ToF-SIMS), XRD, FTIR, and Raman spectroscopies. Similar organic and inorganic materials characteristic of these time periods were identified. The pigments of interest found in both paint generations were botallackite and atacamite polymorphs. This suggests a shift from natural mineral sources to synthetic copper-based pigments for these larger architectural projects.
Keywords: Raman; SEM-EDX; ToF-SIMS; cultural heritage; multivariate curve resolution; polymorph.