For example, the central price of Bank of China is 345.00 yuan per gram. If you want to buy it, it will be 345.4 yuan per gram. This is the bank’s selling price (the price it sells to you). , on the other hand, if you want to sell, you have to sell it at 344.6 yuan per gram, which is the buying price the bank gives you (the price the bank buys from you