Materials and techniques used in the manufacture of painted sculptures at Fushan Temple (1595–1882 AD), Heyang County, Shaanxi Province, China

The painted sculptures in ancient Chinese folk temples are important traditional folk painting art forms, and it is of great significance for painted sculptures conservation to study the materials and techniques employed in their production. In this study, firstly, the samples from eight different colored painted sculptures were collected at Fushan Temple (1595–1882 AD) in Heyang County, Shaanxi Province, China. Secondly, the surface morphology and cross-sectional structure of the painted sculptures were investigated using optical microscopy and scanning electron microscopy (SEM). In addition, qualitative and semi-quantitative studies of the elemental and physical phase compositions of the materials used in the manufacture of the painted sculptures were conducted by X-ray diffraction (XRD), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). The results showed that the painted sculpture samples from Fushan Temple comprised a pigment layer, white powder layer, fine clay layer, and coarse clay layer from the outside to the inside. The white powder layer was made of chalk, with functions in color development and leveling. The fine clay layer comprised quartz and other sand particles with small grain sizes. The coarse clay layer comprised feldspar and cotton silk, with larger grain size. In addition, the pigments used in the painted sculptures were chrome red, lapis lazuli, phthalocyanine green, earth green, amorphous carbon black, iron oxide red, and pyrite. The green pigment was earth green in the early stages but it was later repainted with phthalocyanine green mixed with some lapis lazuli pigments for toning. In addition, the dark green and brown pigments comprised mixtures of amorphous carbon black and phthalocyanine green, and amorphous carbon black and iron oxide red, respectively.