I tested 2 ways of improving iron smelts by treating the ore, roasting the ore and using snail shells as a flux. Then finally I recycled old slag to see if it would produce any more iron. The first way was to roast the ore before smelting. This drove off the moisture and volatiles in the ore as well as burning off any sulfur present. The resulting ore produced a higher yield of iron than normal (33g iron as opposed to about 15g iron as usual for the same volume of ore, charcoal and time). Next lime was added to the smelt as a flux in the form of snail shells. The theory was that the lime would lower the melting point of any silica in the ore to make a runnier slag and help the iron come together more. The result was very bad, no iron was produced apart from 1 or 2 prills. I suspect the ore is already basic in chemistry and adding a basic flux in the form of lime made it so basic that the slag was too viscous. The ore probably won't benefit from a basic flux but might benefit from an