Smelt Iron Slag from Magnetite in Basalt Deltas

Locate and Mine Magnetite

Magnetite spawns naturally in basalt deltas biomes. Mine it with a pickaxe and collect the ore blocks.

Heat Magnetite Near Lava

Place magnetite blocks adjacent to or near lava pools. The heat from lava causes magnetite to transform into smoldering magnetite—a more valuable ore variant. You can speed this up by placing blocks directly next to flowing lava or in lava-rich areas.

Smelt Smoldering Magnetite

Once transformed, smelt smoldering magnetite in a furnace or blast furnace to obtain iron slag. Iron slag serves as a useful intermediate material for crafting and smelting.

Automate the Process

For efficient farming, create a setup where magnetite blocks are positioned near lava flows. Use hoppers and furnaces to automate collection and smelting. The basalt deltas provide abundant lava, making this a reliable iron production method in the Nether without needing to find traditional iron ore.