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[Mineralogical and spectral characteristics of copper pectolite]
Chen Zheng1, Zuo-Wei Yin, Ke Yin
1Institute of Jewellery, China University of Geosciences, Wuhan 430074, China. zhengchen-gem@qq.com
Abstract:
Copper pectolite, a type of pectolite with blue stripes, is a rare gem material with a great market prospect. Mineralogy and genesis were investigated using X-ray diffraction (XRD), Fourier infrared absorption spectroscopy (FTIR), Raman spectroscopy (Raman), scanning electron microscopes (SEM) and ultraviolet-visible spectrometer(UV-VIS) to understand the mineralogical compositions and characteristics of the parts with different color. XRD, FTIR and Raman result showed that copper pectolite is composed of pectolite and minor calcite, consistent with the result of SEM. FTIR showed that an obvious band at 1 500 cm(-1) with 883 and 710 cm(-1) occurred on the white part that contain minor calcite, while the band was absent on the blue part. UV-Vis absorption spectroscopy analysis showed that the blue part has 640 nm absorption band in the UV area that indicates containing elements Cu. The different mineralogical compositions of the white and blue part indicate their different geological conditions.
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