Iron bolts are the third-weakest bolts, stronger than blurite bolts. They may be fired by any crossbow.
Iron bolts may be created by players. First, a player must smith unfinished iron bolts. This requires a Smithing level of 18, and for each iron bar a player smiths they will get 10 unfinished iron bolts and 25 Smithing experience. Then a player must attach flights to the bolts. Attaching flights to each bolt requires a Fletching level of 39 and 1 feather, granting 1.5 Fletching experience per bolt.
Iron bolts may be tipped with pearl. To tip the bolts with pearl, a player must have a Fletching level of 41 and use pearl bolt tips with the iron bolts, granting 3.2 Fletching experience for each pearl bolt tip attached and making the iron bolts into pearl bolts. Pearl bolts can then be enchanted, but more information on enchanting them is available under pearl bolts.