I've been playing for about a week on build 44b, and I've yet to find any starter ores. The biome I spawned in had Diorite at ground level, so I dug/tapped through that a bunch before learning that there is little-to-no ore above 130. Since then I've done exploratory mines in 13 different biomes, plus a few minutes in creative. I've been operating under the assumption that within a given named biome (eg "Forest1") the stone will be the same throughout for any given y-value, +/- a few where the transitions are. My observations support that so far; is that correct? I've noticed that within a biome, there is usually a stone transition at about y=135, +/- 5. This means that checking the surface stone type is pretty worthless, right? It will almost always change before you get deep enough for ores. (Unless there is some pattern to what the second stone will be based on the first stone?) I did find a biome where the transition didn't happen until 97, but it wasn't a useful rock on either side. After the 13th biome with still no igneous intrusive rocks below 135, I got frustrated and started a creative world specifically to figure out what stones are in what biomes. I spawned in the middle of a Forest1 again, punched downwards, and was surprised to find completely different stone than in my survival world. Are the very definitions of the biomes randomly determined from the seed? That would explain why I haven't seen any guides about which stones correspond to which biomes, certainly. But if so, is a Forest1 at least consistent throughout a single world? After the first few mines, my method evolved to: 1) Find two new biomes 2) Dig a staircase at the seam between biomes 3) Stop once I have seen both biomes transition to the second stone Do I need to dig further to have any chance of finding igneous intrusive rocks below 130? (ie, the second layer is never of that type?) Do the later stone transitions follow the same pattern of generally being at about the same height +/- 5 in each biome?