Characteristics of FTIR Spectra of Biogenic Calcites in Precious Red Coral

• 责任者：Fan Luwei (Yifu Museum ; China University of Geosciences ; Wuhan 430074 ; China) ; Yang Mingxing
• 刊名：Journal of Mineralogy and Petrology
• 出版年：2010
• 卷期：30(2)
• 关键词：方解石 ; calcite
• 页码：p.21-24
• 图表：3 illus., 2 tables, 11 refs.
• 分类号：0700
• issnNo：ISSN1001-6872
• isbnNo：CN51-1143/TD

The FTIR spectra of calcites from three species of precious red corals are measured and comparatively analyzed. Results show that the mineral composition of the precious red coral is of high-Mg calcite. The υ₂, υ₃ and υ4 vibrational frequencies of the precious red corals has the mean value of 875.5, 1 426.5 and 714.2 cm^-1_, respectively, which is about 2.5, 6.5, and 6.2 cm^-1 higher than that of calcites of natural inorganic calcites. The unusual characteristics of υ2, υ3 and υ4 vibrational frequencies of calcites of the precious red coral are probably resulted from the low crystallinity, crystal lattice distortion and nanometer size of calcites.