Often it's easier for a Promethean Complex to just be built over a mine in the first place. If that's not an option then the Enlightened have advanced machinery and indentured servants that allow them to mine otherwise deposits of ore inaccessible to the other great powers. Even mines that aren't fiscally viable are opened given the insatiable hunger the Covenant of the Enlightened have for coal and raw materials.
This set contains:
Wild West Exodus