Tutorial:Cobblestone farming

Cobblestone farming is the technique of using a cobblestone generator to produce cobblestone without damaging the terrain. Cobblestone generators work on the principle that when a lava stream comes into contact with water, the lava is turned into cobblestone. Please note that this isn't possible in the Nether, due to water evaporating upon placement. This fresh cobblestone then prevents the two streams from touching. When this fresh cobblestone is removed, the two fluids produce another piece of cobblestone. Variants of the generator can also produce stone, but this is generally trickier, because for stone, the lava must enter the water from above.

Many generator designs exist, but the simplest way is to make a five block long trench with a one block gap in the middle. Then, place water in it at the end closest to the hole and lava at the other end. This creates cobblestone where the fluids meet.

When producing cobblestone, one must be careful not to let the flowing water touch the lava source block. Doing so destroys the lava source, converting it into obsidian. A basic understanding of fluids is helpful to prevent this. If you place a stair into the water source (flat side to the lava), this prevents the water from flowing over the lava source, but the cobblestone still forms where flowing lava touches the waterlogged block. Placing a non-flammable block over the lava helps prevent the cobblestone item from being destroyed by the lava when you mine it, as well as keep you from falling into it.