It only shows which option is active, you have to go to FORGE, select one of the 3 options on top, then open METALWORK, fill the bar with ORE BARS (with % buttons), and then pres CAHRGE using LEGENDARY SPIRIT AURA
Then there should be message about mines with the button to transfer you directly to it just click on the wooden bars blocking entrance and they will be destroyed...if it does not work then I assume it is a bug
