Abstract: All of the historical silk textiles were dyed with natural materials, most of which were vegetable dyestuffs. In present studies, seven vegetable dyes were identified by non-destructive method-miniature spectrometer with fiber optics. This method was successfully applied to acquiring the ultraviolet-visible absorption spectra of madder, Amur cork, pagoda tree, sappanwood etc. In addition, miniature spectrometer with fiber optics was also used for light-fastness evaluation of vegetable dyes. Seven samples have been exposed in Xenon lamp at4.32×104w/m2, and the results indicated that the light-fastness of Amur cork was lowest, whereas the light-fastness of indigo was much better. Thus, miniature spectrometer would serve as a non-destructive technique for quick analysis of natural dyestuffs; also, this method can help to slow down the effect of light-ageing for the historical silk textiles during a period of exhibition and conservation through establishing suitable light environment.

Key words: miniature spectrometer with fiber optics, vegetable dye, identification, light-fastness