STUDIES ON THE IDENTIFICATION OF PIGMENTS ON RELICS AND THE ANALYSIS OF COLOR CHANGES BY FIBER OPTICS REFLECTANCE SPECTROSCOPY

In recent years, modern instrumental analysis techniques have been increasingly used to analyze and identify relics. For those cherished and unique works, the analysis techniques used should be non-destructive. This is a hard nut for us to crack. With our self-developed Fiber Optics Reflectance Spectrophotometer, a fiber optics reflectance spectroscopy (FORS) technique is used to identify the pigments on color relics and to monitor the change of the color non-destructively. The pigments on the color relics in Dazu Stone Sculpture Area, Sichuan Province and in the tomb of King Qianyang of the Ming Dynasty in Xiʹan have been measured and their chromogenic components determined. The comparison between the result of FORS and those of X-ray diffraction analysis and X-ray fluorescence tells that FORS is both simple and reliable. Also, the color change of red lead in an imitated environment has been measured, setting up a quick and non-destructive technique to monitor its color change.