Abstract: "Lightbox Jewelry" synthetic diamond is the first brand product of synthetic diamond released in September 2018 by De Beers, which has several series of colours including colourless, pink and blue. The Lightbox Jewelry synthetic diamond jewelry samples have been collected and systematically investigated by using microscopic observation, DiamondView^TM fluorescence imaging and spectroscopic techniques. The results show that the main stones of Lightbox Jewelry are CVD synthetic diamonds. The gemmological characteristics of the samples are as follows: IR spectra showed they were type Ⅱa; 596/597 nm doublet emissions appeared in all samples, 737 nm doublet were present in some of the samples; The existence of 596/597 nm doublet emissions indicated that the samples had not undergone the post-growth HPHT treatment. In addition, for pink samples, absorptions at 595, 637 nm and 741 nm were recorded. It was speculated that the pink samples have been received irradiation annealing treated. For blue samples, their UV-Vis absorption spectra showed a broad band at 621 nm and a absorption peak at 741 nm, and their IR spectra showed 9 287 cm^-1 peak, speculating that the blue samples had undergone the treatment of irradiation. The melee-size colourless diamonds of Lightbox Jewelry were also tested and studied. It was also found that most of the melee-size diamonds are mainly HPHT synthetic diamonds mixed with a few natural diamonds.