一种体色呈蓝色的铍扩散处理蓝宝石

Beryllium-Diffused Treatment Sapphire with Blue Body Colour

针对近期市场上出现的一种体色呈蓝色或淡蓝色的Be扩散处理蓝宝石,采用EPMA,LA-ICP-MS、激光拉曼光谱仪、UV-NIS分光光度计等分析测试仪器,对50粒Be扩散处理蓝宝石样品的化学成分、拉曼光谱、UV-NIS吸收光谱特征进行了研究。测试与研究结果表明,这种Be扩散处理蓝宝石样品中,Be的质量分数最低为5.28×10-6%,最高为17.51×10-6%,平均为8.74×10-6%;其内普遍含有形态各异的斜锆石熔融或假象包裹体;由于Fe3+离子d-d电子跃迁,导致形成了样品的吸收光谱a带(377,386,451 nm)。在高温条件下,由Be扩散诱生的色心可能是导致蓝色蓝宝石呈色的主要缘由。

A type of beryllium-diffused treatment sapphire with blue or light blue body colour has recently appeared on gem markets. The chemical compositions, Raman spectrum and the characteristics of UV-NIS absorption spectrum of 50 beryllium-diffused treatment sapphires samples are investigated by using EPMA, LA-ICP-MS, laser Raman spectrometer and micro-optical fibre spectrometer. The testing and research reasults show that the minimum mass percent of beryllium is 5.28× 10^-6 % and the maximum is 17.51 × 10^-8 % and the average is 8. 74 × 10.8% in the beryllium-diffused treatment sapphire samples. Generally, the samples contain all forms of baddeleyite melting or pseudomorph inclusions. Because of d-d electron transition in the FeZ^3＋ ion, the absorption spectrum band a （377,386,451 nm）of the samples is formed. With the high temperature, the beryllium-diffused and induced vacancy colour center may result in the blue colour of sapphire.