Smooth Stone is a Cobblestone block that goes through the smelting process twice. Therefore, to get Smooth Stone in Minecraft ...

Place the stone back into the furnace in the upper slot and it will yield you Smooth Stone with the same 1:1 ratio. The most efficient fuels to use in the furnace are coal and charcoal.

Arrange the Stone Blocks: In the crafting grid, place four stone blocks in a square formation. Specifically, place one stone ...