Gold can't be returned as soon as it is bought back. If the other party promises to return the goods unconditionally, it can return them. Otherwise, the merchant can only claim to terminate the sales contract if there is fault or other breach of contract, otherwise it can't return the goods.

If there are any quality problems, you can't return them. You can only say you sold it to him. Once jewelry reaches customers, it can only be circulated at the price of raw materials. If you want to sell it, the jewelry store can recycle it everywhere, but you should remember to bring the receipt so that people won't think you are stolen goods.