Synthetic Pink Sapphire

Natural pink sapphire,especially padparadscha sapphire,is one of the precious kind in fancy sapphire and very expensive because of its rare yield.In the paper,it is discussed that the synthetic pink sapphire coloured by Ti³⁺ ions is gained as the by-product while synthetic Ti-doped sapphire laser crystals are studied,including the control method of the Ti³⁺ valence during the process of crystal growth.The experimental process and method of synthetic pink sapphire grown by the czochralski method are also introduced.The results show that the synthetic Ti-doped sapphire sample with obvious purple could change to the synthetic pink sapphire heat-treated for 48 hours at 1 920 to 1 995℃ and in the reducing atmosphere of hydrogen,whose colour is similar to that of the padparadscha sapphire.Finally,the gemmological characteristics of the synthetic pink sapphire sample are also analysed by using the conventional testing and energy-dispersive X-ray fluorescence spectrometry.