With Smeltery, players can forge premium alloys that can be made into unique weapons and armor, and be sold to NPC merchants for gems.
Smeltery requires a workstation called the Forge, which can be built as such:
When smelting, there is a small chance that you’ll produce a rare version of the ingot or crystal. When crafting items with the rare material, you increase the chance of crafting a Masterwork item. Masterwork items obtain improved and sometimes new stats.
To learn the details of the Smeltery skill, complete the quest “Apprentice Smelter” from Darnov in New Nauru, or a Blacksmith citizen in one of your Towns!
Curious about the characteristics of your alloy? Take a look at the ingredients; if the alloy contains iron, the characteristics will be based off of iron, and so forth.
Build Guide:
https://mc-atlas.com/model/smeltery