Iron ore, like all other mined rocks, respawns at a rate inversely proportional to the number of people in the rock's RuneScape world. If the world is empty, the ore respawns in 10 seconds; if it is full (with 2000 players), it respawns in 5 seconds. Thus the respawn rate of iron ore is seconds, where x is the number of players in the world. A table of respawn rates is given below.