When someone learns that I survey in underground mines, they very often ask, "What's it like to survey underground?" This article will discuss the similarities and differences between surveying in the sunlight and surveying deep underground. In Alabama, where my coal mining experience has been ...
Underground mining is selected when the rock or mineral is so far to reach using surface mining. Shaft mining is the kind of mine that you normally see in movies where the miner travels straight down into a profound, dark tunnel until he reaches the base.
Dig any way you want, just do not dig straight down; you might fall into a pit, or into lava. At the bottom of every world is a layer of unbreakable bedrock. Ores in Minecraft are most commonly located only a few blocks above this layer, so dig until your character's y-coordinate is 13 or so.
A tunnel is an underground or underwater passage that is primarily horizontal. Relatively small-diameter ones carry utility lines or function as pipelines. Tunnels that transport people by rail or by automobile often comprise two or three large, parallel passages for opposite-direction traffic, service vehicles, and emergency exit routes.