Board Thread:General Mod Discussion/@comment-27752412-20160221173323/@comment-26116279-20160222012831

I'd recommend something similar to what MilkMC said, but instead of 6 blocks between tunnels use 2, that way you see everything and there's not a chance that mithril ore is hiding in the walls. Also if you come across lava lakes you can sometimes empty them and find some mithril, though i doubt that's very common.