So the tooltip for mining says "small chance of discovering ..." and then gives a list of the resources you know about that require mining to be added to your resource pool. My question (and it'll probably take someone looking deeply behind the scenes) is if I take a random hill and mine it and then switch to a windmill and then mine it again and then switch to a windmill again and then... is there a chance each time I put a mine there that a resource will be discovered in the mine, or did they just word the tooltip badly? Basically, in every game I've played so far, either coal or aluminium had exactly ONE spot in the world where it was available, and since coal is important to railroads (whatever happened to diesel trains?), and aluminium is important to modern tanks (which require COMPOSITES to unlock, so why do I need aluminium?); I want to be able to get some in my territory without having to fight for it.