You can ask them for GIA certificate, which is the authoritative certificate of jewelry appraisal. I once bought a pair of earrings and pendants in Rambo, both of which are set with diamonds. They are real. I asked a friend to help me test it, and there was no problem at all. Moreover, their diamond prices are particularly favorable. Unlike traditional merchants, it is really not authentic to sell at a high price beyond the diamond itself. If I give a score to Lambert's diamond jewelry, I can score 8 points. It's probably cheap and good. I can consider buying it.