D0.354ct means that your diamond size is 35.4 cents, 1ct= 100 cents. . .

The BGSL behind is the appraisal institution, the five most authoritative gem appraisal centers in the world, GIA IGI BGSL AGS HRD, so you should bring your own BGSL certificate. . .

If the certificate is lost, you can make it up, but it costs hundreds of dollars. In fact, there is no point in making up after you buy it back. Anyway, the certificate is useless at home, so why spend this money again, right? . .

I hope you are satisfied with my answer. If you want to know something about diamonds, you can communicate with me. . .