Deepslate is the hard, dark grey rock that makes up the deep underground in Minecraft, added in the 1.17 Caves & Cliffs: Part I update. Since the 1.18 terrain overhaul, deepslate fills nearly every layer from about y=0 down to the world bottom at y=-64, replacing ordinary stone in a gradient transition zone between y=0 and y=-8. The texture is a moody dark grey with subtle vertical striations and an oval pattern on its top and bottom faces, and deepslate has its own deeper footstep, mining, and breaking sounds that signal the descent into the lower world.

Deepslate needs at least a stone pickaxe and is twice as hard as stone (hardness 3 versus 1.5), so it takes roughly twice as long to mine with the same tool, though its blast resistance of 6 matches stone. Mining deepslate without Silk Touch yields cobbled deepslate — the deep-cave equivalent of cobblestone — while Silk Touch returns the block itself; smelting cobbled deepslate in a furnace turns it back into deepslate. Deepslate is the base of a full building family that includes polished deepslate, deepslate bricks, deepslate tiles, chiseled deepslate, and their slabs, stairs, and walls, making it the go-to material for dark dungeons, gothic chapels, and underground cathedrals.