Metal mine

Cost of the 1st level:

6015 CRP 1.5
It is the main supplier of raw materials for the construction of bearing structures for buildings and ships. Metal is the cheapest raw material. But it requires a lot. Large deep mines require a lot of energy.
+ 18 * level * 1.1 to the power of level
- 10 * level * 1.1 to the power of level
Comparison by level
Lvl Production of metal Energy
1 19 -11
2 43 -25
3 71 -40
4 105 -59
5 144 -81
6 191 -107
7 245 -137
8 308 -172
9 381 -213
10 466 -260