I don't know about Shanghai, but I know a few about Beijing. You can't do it online. I haven't seen it online yet. There are still many fakes in the jewelry market and antique market, not to mention online.

There is a Jiaozi jewelry store in Longde Square, Changping District, Beijing, which sells amber and tourmaline with good quality. It is also pure natural. I think some Buddha heads are really beautiful and beautifully carved. It is said that it is made in Hong Kong, and there are many bracelets, including beeswax, Jin Po, Sherpa and Huapo. If you have a chance to come to Beijing, you can go there.