Generally speaking, merchants like to set diamond rings with gold. But it is generally not allowed to exchange diamond rings for gold. Because the profit of diamond ring is higher than that of gold.

Normally, you can't exchange gold for a diamond ring. On the one hand, the price of diamond ring is complicated, unlike gold, which has a clear price every day. On the other hand, diamond rings are more profitable. If you exchange an equivalent diamond ring for an equivalent gold, the merchant will definitely not want to exchange it if he earns less. Usually only diamond rings can be exchanged for diamond rings, and gold can be exchanged for gold.