Minecraft wiki entry for Nether_Wastes, associated text: The Nether Wastes is a barren biome composed of mostly netherrack. It has extensive lava seas with glowstone blobs hanging from the ceiling. Blobs of nether quartz, nether gold ore, and blackstone generate in the wastes (where ore is most visible) with the more rare Ancient Debris found unexposed within the terrain. Gravel and soul sand are found among its coastlines.