文献类型：期刊文献

英文题名：Component Analysis and Identification of Black Tahitian Cultured Pearls From the Oyster Pinctada margaritifera Using Spectroscopic Techniques

作者：Shi, L.[1];Wang, Y.[1];Liu, X.[1];Mao, J.[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai, Peoples R China

年份：2018

卷号：85

期号：1

起止页码：98

外文期刊名：JOURNAL OF APPLIED SPECTROSCOPY

收录：;EI(收录号：20242616438650);WOS:【SCI-EXPANDED(收录号:WOS:000430006000016)】；

语种：英文

外文关键词：black Tahitian cultured pearl; Raman spectroscopy; UV-Vis-NIR reflectance spectroscopy; X-ray fluorescence spectroscopy

摘要：Raman spectroscopy, ultraviolet, visible, and near infrared (UV-Vis-NIR) reflectance spectroscopy, and X-ray fluorescence (XRF) spectroscopy were used to characterize black Tahitian cultured pearls and imitations of these saltwater cultured pearls produced by gamma-irradiation, and by coloring of cultured pearls with silver nitrate or organic dyes. Raman spectra indicated that aragonite was the major constituent of these four types of pearl. Using Raman spectroscopy at an excitation wavelength of 514 nm, black Tahitian cultured pearls exhibited characteristic 1100-1700 cm(-1) bands. These bands were attributed to various organic components, including conchiolin and other black biological pigments. The peaks shown by saltwater cultured pearls colored with organic dyes varied with the type of dye used. Tahitian cultured and organic-dye-treated saltwater cultured pearls were easily identified by Raman spectroscopy. UV-Vis-NIR reflectance spectra showed bands at 408, 497, and 700 nm derived from porphyrin pigment and other black pigments. The spectra of dye-treated black saltwater pearls showed absorption peaks at 216, 261, 300, and 578 nm. The 261-nm absorption band disappeared from the spectra of gamma-irradiated saltwater cultured pearls. This suggests the degradation of conchiolin in the gamma-irradiated saltwater cultured pearls. XRF analysis revealed the presence of Ag on the surface of silver nitrate-dyed saltwater cultured pearls.