Energy

There is two type of mineral: charcoal and turnium.

Charcoal
It's use to create some ligth and heat for the city. The charcoal is use also to heat the turnium to make it turn.

Turnium
The turnium is the seconde most use mineral, its generally use for every mechanic systeme. When you heat at 50°C he will turn on himself. The hotter it is, the faster it turns.

Chaturnvite
The savant melt some charcoal with some turnium and they create the chaturnvite. Its better than the turnium in term of speed, life time, and of heat. Use in big mechanic systeme and in different transport like the citrain.