Superheat Item

Superheat Item is a non-combat Magic spell used to smelt ore without a furnace. It can be used by both free and member players. While wielding a fire, lava or steam staff, it takes one nature rune per cast. Without any of the aforementioned staves, it takes four fire runes, and a nature rune. Casting Superheat Item creates only one bar, and cannot be cast upon noted ores. The ore amount required is the same as if you were smelting the bar in a furnace.

The same Smithing level is required to superheat ore as the level required when smelting in a furnace. For example, your Smithing level must be 50 if you wish to superheat the ore for a mithril bar, and to superheat ore for a rune bar, your Smithing level must be 85.

53 XP is rewarded to you in the Magic skill, and the normal Smithing experience is rewarded as if you were smithing the bar in a furnace.

Smelting a bar that requires coal is a little different, for you cannot click on the coal itself, but instead you must click on the primary ore for the bar that you wish to create. For example, to smelt a mithril bar, you must click on a mithril ore in your inventory in order to superheat a mithril bar.

Furthermore Superheat Item guarantees a one-hundred percent success when smelting iron ore into an iron bar, whereas when smelting with a furnace only yields a fifty-to-eighty percent success rate.

Superheat Item cannot be used to make jewellery or cannonballs, but does allow one to create gold bars  as well as silver bars  and any other metal bar. Please note that to get the full 56.2 Smithing experience per gold ore you must be wearing Goldsmith gauntlets.

Attempting to cast Superheat item on a non-ore object will result in the message You need to cast superheat item on ore.

Casting at mines
Superheat item is sometimes used when mining coal and either iron, mithril, or adamantite. Superheat item can free up inventory space by using up coal to create bars. Eventually, a near-full inventory of bars can be banked.

It is argued that it is most beneficial with iron as it gives 100% success (instead of 50%-80%), so this means fewer mining/bank/furnace trips.

Other factors to be considered for any ore is weight and running. The bars weigh slightly less than the ore, so you can run for longer. But you can carry 2 fewer bars to the bank (fire/nature rune(s)).

If players plan to mine the coal as well as the metal that is required to make the bars, and the mining site has both coal rocks and that of the relevant metal, the time saved could be considerable. An almost full inventory of bars could be made in one trip rather than requiring one trip for an inventory of ore and several loads more for the coal to smelt it with.

Another possibility is to cast at the Coal Trucks. Example using mithril: Instead of 5 to 7 trips to empty the coal trucks in the Seer's Village Bank, you can take 22 mithril ore, nature runes and an equipped fire staff or better and leave 4 slots open, plus the space for your pickaxe. Repeatedly fill the slots from the coal trucks and cast Superheat Item. In this way only two trips to the bank are required for mithril.