# What were the main ingredients to make iron and eventually steel?

Well you need $\text{ferric oxide}$, and some $\text{coke}$, and a big furnace........
$F {e}_{2} {O}_{3} \left(g\right) + 3 C O \left(g\right) \stackrel{\Delta}{\rightarrow} 2 F e + 3 C {O}_{2} \left(g\right)$
Steel production is a big, and very capital intensive business. Quantitiies of ferric oxide, and carbon monoxide and heated in a so-called $\text{blast furnace}$. When I was much younger I was taken to see some of these, and you are very impressed by the scale and the output of these operations. Given the blast furnace, the main ingredients are (i) $\text{ferric oxide}$; and (ii) $\text{coke}$, which can be oxidized up to give $C O$, which effects the reduction of the iron ore to iron, and maybe later steel.