I bought about 10 quarries before last reset. This game I bought 1. Seems like by the time I can buy them I'm already mostly maxxed on mineral production and the steel cost of buying one makes me want to avoid the cost.
Almost every other building I build I want to max, but not this one, am I missing something?
Best Answer
The quarry has two effects: improving the mineral production and produce a bit of coal. Other then that, it doesn't do anything. But I found that coal was a resource I was lacking during midgame, so that's why I built quite a lot of them myself. So the mineral boost is not that necessary, but the little bit of coal is.
From the source code: