Non-destructive Testing of Golden Saltwater Pearls

Golden saltwater pearls and colortreated golden pearls were tested and analyzed. According to the magnify observation, the surface of golden saltwater pearls were smooth. The surface of color-treated golden pearls was destroyed; color was enriched in local area. In Raman spectra, fluorescence background of colortreated golden pearls was significantly higher than that of golden pearls. The intensity of 275 cm-1 Raman of golden saltwater pearls band was more obvious and stronger than that of colortreated golden pearls. In UV-visible absorption spectra, there were characteristic absorption peaks of 284 nm and 357 nm, and no characteristic absorption peaks in the spectra of colortreated golden pearls. According to the differences of magnify observation, Raman and UV-visible spectra between golden saltwater pearls and colortreated golden pearls, they could be quickly and effectively set apart without any damage．