Smithing is a skill through which players create a wide variety of metal items from ore and metal bars. It is the companion skill of Mining, which generates raw materials used in Smithing. Ores acquired from Mining are smelted into metal bars at furnaces and then hammered into items at anvils. Many smithable items are useful in the training of a number of other skills such as Crafting and Fletching.
Smelting is the process of extracting a metal bar from a metal ore. To obtain a metal bar, a player must use an ore of the desired metal with a furnace. Some metals require multiple ores and some require coal to be added to the furnace to raise the furnace's temperature. Smelting steel, mithril, adamantite or runite bars requires one coal per bar.
Metal bars can be smelted by either using ores directly on a furnace or by clicking on the furnace, right-clicking on the desired bar to smelt and selecting the number of bars to smelt.