Minerals are a scarce material on this planet, on the one hand, because of the large consumption, and on the other hand, because many minerals are buried deep underground, it is not easy to dig.
Copper ore and iron ore are relatively abundant on the surface or underground, while other minerals are relatively scarce, and mining engineering is also very difficult. Generally, it is best to bring more torches when digging, and also dig a good passage to facilitate the return.
Diamond:
Gold mine:
Copper mine: