Generally, it is red, indicating that the transaction is made at the price of active purchase (the external market is rising) (or the current transaction price is higher than the previous transaction price);

Green means that the transaction is made at the price of active selling (rising internal market) (or the current transaction price is lower than the previous transaction price);

White indicates that both buyers and sellers have made a transaction at the latest price (both domestic and foreign markets have increased or remained unchanged), or the transaction price is the same as the previous transaction price.

Specifically, observe the relationship between the number of inner and outer disks and the color change of hands.