The tourmaline necklace I bought is getting yellow? Looking at the transparency has also decreased, it seems to be more and more turbid? Why? Is Tangshan a place that can be identified?

Basically, it is certain that the bracelet you buy is injected.
Thamanels are very complicated borosilicate, which are inorganic. It is impossible to change because of sweat. You can only explain the yellow. This kind of tourmaline bracelet is a glue. Because of the extensive development of gem cracks and parcels such as tourmaline, pure and indifferent tourmaline prices are very high, and they are generally used to make noodles. The worse is used to make beads and flowers.
The grinding beads are fully automatic equipment, so when making beads or flowers, in order to improve the yield, it is filled with organic resin in advance, and then it looks transparent and beautiful. However, organic resin will be eroded in acid and alkali and deteriorate, so the transparency of yellowing will gradually decrease. The tourmaline beads and sculptures of this kind of glue are equivalent to the emerald B goods. They only have jewelry value and do not have jewelry value.
It specific situations you can consult the local Morgan Jewelry.