Requirements- lvl 30 mine, 30 smelting i recommend mithril or addy pick-sorry low lvl people
mine coal in barbarian village or al kharid mine
mine iron in al kharid mine (mine silver there are 5 silver rocks in the mine)
smelt at the place between bank and scimmy shop
do this until you have 200 steel bars
sell at grand exchange you will have 100+k
also sell ur silver bars i usually get get 50 bars of silver
each bar of silver is worth 350gp and steel bars is worth 750