I finished the demo but went looking around found a furnace and forging area. (i presume this is soon the be implimented though am gonna mention this incase you didn't know or someone else playing wants to know) you can get infinate iron ore/ingots here just open and close the same furnace multiple times the smelting is slow enough that the ore multiplies if you go fast enough to grab some ore. In order to stack bars you have to do this method as you can not hand stack them. Also the pink ore (forgetting the name) you can not smelt