一种浅蓝色蛋白石的宝石学特征与呈色机理研究

Gemological characteristics and Colouring Mechanism of a light blue opal

利用宝石显微镜、折射仪、静水称重法、红外光谱仪、X射线能谱仪及紫外-可见分光光度计对浅蓝色蛋白石样品进行相关测试,结果显示:样品外观呈浅蓝色,玻璃光泽,均质体结构,折射率1.45(点测),相对密度2.09~2.11,红外光谱显示成分为蛋白石,通过X射线能谱仪测试得出含铜(Cu),紫外-可见分光光度计测试在480nm处有吸收,呈色机理为Cu^2+以类质同象形式替代Si^4+产生空穴色心所致,该浅蓝色玉石样品为天然蛋白石。

Sapphire microscopy,refractometer,hydrostatic weighing method,infrared spectroscopy,X-ray energy spectrometer and ultraviolet-visible spectrophotometer were applied to test the light blue opal samples.The results showed that the sampled had a light blue appearance,glass gloss,homogeneous structure,refractive index of 1.45 (point measurement),relative density of 2.09-2.11,infrared spectrum of opal,copper (Cu) determined by X-ray energy spectrometer,and the absorption occured at 480 nm.The colouring mechanism was due to the formation of hole colour centers by substituting Cu^2+ for Si^4+ in the form of isomorphism.The light blue Opal sample were natural ones.