China Univ Geosci, Sch Mat Sci & Technol, Beijing 100083, Peoples R China
; Guilin Inst Technol, Dept Resource & Environm Engn, Guilin 541004, Peoples R China
; China Univ Geosci, Coll Gemol, Beijing 100083, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China
Seawater cultured pearl was studied by high resolution fourier transform infrared spectroscopy (FTIR) both before and after having been heated at 160 centigrade degree. The results of FTIR indicate that the main material in both samples is aragonite (CaCO3). But compared with the spectra of the seawater cultured pearl, there are some changes that happen in that of the heated sample. Some other peaks arise in the latter. And the intensities of these peaks increase with the heating time. Differential Thermal Analysis (DTA) curve of the seawater cultured pearl shows that seawater cultured pearl has no change between 25-160 degrees C except absorbed water evaporating from the sample. All these evidences prove that besides aragonite, there exists something else in the seawater cultured pearl. This component was determined to be pahuite by FTIR spectroscopic analysis. X-Ray Diffraction (XRD) analysis of the same sample came to the same conclusion.