Identification Characteristics of Undisclosed CVD Synthetic Diamonds Found Recently by NGTC

Early in 2012，NGTC labs in Shenzhen and Beijing investigated some naked and embedded diamonds which included some undisclosed CVD synthetic diamonds.It was found that these gemquality CVD synthetic diamonds are difficult to distinguish from natural diamonds by normal microscopic observation.However，they can be effectively identified with the help of some advanced analytical techniques，such as PL（Photoluminescence）and DiamondView^TM.The experiments show that the line at 737nm in the PL spectrum and the bluish green fluorescence，the blue phosphorescence together with characteristics of multi－layered structure in DiamondView^TMare the characteristics of these CVD synthetic diamonds.