Aluminium

Aluminium is a metal added by various mods.

GregTech
The main source of Aluminium is Bauxite Ore, but it can be aquired from electrolyzing various other dusts as well. Aluminium Dust can't be smelted in a regular furnace, but requires a Blast Furnace or an Industrial Blast Furnace to be smelted into ingots. Ingots and plates are mostly used as replacements for Refined Iron ingots and plates, but are required in some other recipes as well.

Immersive Engineering
Aluminium is created by smelting Bauxite Ore.