What kind of copper is used for divination?

Ancient copper coins are generally used.

The method of fortune-telling is not just to use copper coins. Nowadays, people use dry copper coins for divination, as if only dry copper coins are allowed. This is a wrong view. The method of divination with copper coins has a long history. As long as it is copper coins, you can take coins without copper coins, and you don't have to use dry copper coins. Sincerity is the spirit. The accuracy of divination lies not in the use of copper coins or coins, but in the sincerity of divination. The ancients said: ghosts and gods are incredible. That is to say, if you don't think (sincerely) sometimes, ghosts and gods don't know what they are thinking, so how can you tell from the hexagrams? The secret is now in the hexagram, which is only the forecaster's prediction of the state of the time field, and he doesn't care whether to use copper coins.