So I was doing some data collection on materials for crafting and I noticed some patterns... except in one place.
So the base materials for a metal minor armors are 5 iron ingots for level 1, and goes up one per level (i.e 6 for level 4, 7 for level 6, etc.) until it changes to steel, at which point it starts at one more than iron at 6 steel. This continues with orichalcum starting at 7, dwarven ingots starting at 8, etc.
This holds true for all armor and weapons I've checked so far, EXCEPT for metal legs.
Iron starts at 6 ingots, steel is also 6, but orichalcum is 8. So steel starts one ingot less than it should be. Steel should start at 7.
Not a big bug, but I always feel superior spotting them.