Diamond necklaces are valuable, and regular shops outside will worry that they are ill-gotten gains and will be implicated. They will ask sellers to provide valid purchase invoices, proof of purchase and sellers' ID cards for registration.
If it is an ordinary shop, you can buy this diamond necklace at a low price.
Therefore, if you want to sell at a good price, it is recommended to bring relevant information to a regular store for sale. Generally, you will register information and identify the goods, so that the diamond necklace will get a more reasonable price.