Flux is any material used to aid in the purification of smelted metals and cleaning or joining of metal in welding. it is a Metallurgy term.

Schubert Shui-bark Wang has written:

'Metal losses in iron silicate slags' -- subject(s): Metallurgy, Slag, Flux (Metallurgy)

The name is derived from the Latin word "fluores" with the meaning "which flow"; fluorine minerals were used in the past as flux in metallurgy.

coke is used to reduce oxides in the metal eg 2Fe2O3 + 3C -> 4Fe + 3CO2

D. L. Paulson has written:

'Smelting cement copper in an electric-arc furnace' -- subject(s): Metallurgy, Copper, Flux (Metallurgy), Electric furnaces

'Production of blister copper by electric furnace smelting of dead-burned copper sulfide concentrates' -- subject(s): Metallurgy, Copper, Chalcopyrite