Finding Ore at the Right Depth

Since the world was extended from Y-64 up to Y320, every ore in the game generates in a "triangle" pattern: rare at the edges of its range, most common at one particular height called its peak. Mining at that peak height doesn't guarantee ore in front of you — it's still random per chunk — but it does mean far more of it turns up over the course of an hour than digging at a height picked at random.

Diamond and redstone share the same peak, Y-59, right near the bottom of the world, with diamond generation actually increasing the deeper you go. Lapis lazuli peaks much higher, at around Y0. Copper peaks around Y48, and generates in noticeably larger clusters inside Dripstone Caves specifically. Coal is common across an enormous range, all the way from bedrock up to the build limit, and turns up especially often exposed in mountain stone. Iron generates through almost the whole height range too, with one real gap around Y73 to Y79 where it doesn't appear at all — it's common both underground and in exposed mountain deposits far above ground. Gold favors negative Y, around Y-16, but spawns far more often, and much higher up, in Badlands biomes specifically. Emerald only generates in mountain biomes at all, regardless of depth.

A peak height is a starting point, not a promise, so treat a dry stretch as normal rather than a sign something's wrong. Branch mining is the standard technique for actually covering ground at a target depth: dig one long main tunnel at the height you want, then strike short side tunnels off it every few blocks to expose far more stone than the main tunnel alone ever would. A few focused minutes at the right height consistently beats an hour spent wandering at the wrong one.