Disclaimer: On its own, this adds aluminum to the game in the form of vanilla items (ingots, bits) and creative-only items (metal blocks, chains, scales and so on), but doesn't add new items made out of aluminum! There are no workpieces that can be created out of aluminum with just this mod. This mod is meant to be used as a mandatory/optional dependency with other mods that wish to add aluminum items to the game and require the base functionality of refining it to be already pre-made and ready to be hooked into.

Just like in real life, aluminum metal is a result of processed alumina, which is chemically processed from bauxite rock. Since we don't have the means of processing bauxite rock with modern technology in the Vintage Story universe, several primitive steps involving chemical leaching and smelting will have to be performed to obtain aluminum metal! That being said, this mod would fit somewhere in the mid to end game, considering the materials and equipment needed. If these steps inaccurately reflect the real life processes of aluminum production, well.. I am going to pull the "it's just a game" card. I am also open to suggestions!

This is how you process bauxite to obtain aluminum metal (this guide is also in the game handbook):

Preparation
Plenty of sulfuric acid and limewater will be required to process crushed bauxite into alumina (also known as aluminum oxide). Limewater can also be substituted with lye if that option is available to you. Get all of your dirty pots and have some bloomeries on standby for these steps. Having at least 4 pots and 2 bloomeries ready should be enough to produce alumina at a decent speed.

Production
First, crush some bauxite stones and olivine. If you have a bit of powdered borax lying around, now it's your chance to make good use of it, since it can serve as a flux and help alumina separate into more aluminum metal, though it's an optional ingredient.

For 63 crushed bauxite, 63 crushed olivine, 8 powdered borax, 42 L sulfuric acid, 42 L limewater/lye, and 30 quicklime, you will get 24 aluminum bits (or 18 without borax).

Tip: With just 63 crushed olivine you will only use 7 pieces of alumina and be left with 8 spare pieces, so you can crush 1 more stack of olivine, add 21 extra liters of sulfuric acid and limewater/lye, 30 extra quicklime, and 14 extra powdered borax to get around 60 aluminum bits (or around 45 without borax).

Turn the crushed bauxite into aluminum sulfate through acid leaching with sulfuric acid. The mixture needs to be heated in a pot.

Take the aluminum sulfate and further heat it with limewater/lye in a pot to neutralize it into aluminum hydroxide.

The aluminum hydroxide has to be calcined into aluminum oxide (alumina) at high temperatures, so this is where the bloomery will first come into action. After around a day of waiting, you will get that precious alumina!

Alumina on its own cannot be turned into aluminum metal. It has to be reduced with a highly reactive metal, such as magnesium, through a thermal reaction.

To get magnesium, you will have to undergo a similar process to alumina, except you will take crushed olivine, which is rich in magnesium, and perform acid leaching in a barrel instead of a pot. The rest of the process towards producing magnesium oxide is the same. Olivine requires very high temperatures to react, so it cannot be leached in heated sulfuric acid like you can with bauxite.

Magnesium oxide needs to be further reduced into finely ground metallic magnesium in order to react with alumina. Powdered magnesium is obtained by smelting magnesium-carbide charge in a bloomery. Get calcium carbide by smelting quicklime at high temperatures.

Once you have both alumina and powdered magnesium, they can be mixed in the crafting grid to create alumina-magnesium thermite, or you can also add the powdered borax to create fluxed alumina-magnesium thermite.

Finally, this mixture is further heated in a bloomery to make aluminum bits. Congratulations! Now you can smith these bits into all kinds of aluminum workpieces!

Please contact me if you want your mod on these lists

Mods that use "Aluminum from bauxite":

1. Snowshoes - LivCi
2. Metal Leaf - DPhKraken

Mods that "Aluminum from bauxite" is compatible with:

1. Soap and Lye: Bloom and Lather - Brun
2. Soap and Lye - Brun
3. SmithingPlus - jayu
4. Relic Tools - DPhKraken

Feel free to check out my other mods too!

1. Snowshoes: Travel winter terrain without the slowdown of deep snow
2. Craftable wattle and daub: Adds a recipe for crafting wattle and daub blocks
3. Handy daub: Makes adding daub to wattle fences easier by automatically swapping it to the hotbar
4. Burnable roofs: Allow all flammable roofing to be used as fuel. That's it
5. Splittable stone paths: Split stone path blocks into stairs, slabs and quarters, or combine them back into full blocks
6. Fruit in troughs: Allows all fruit types to be placed in troughs