On a tool belt, the promethium pickaxe can be used to automatically mine rocks containing ores, rocks blocking one's path and rocks in the Stomp boss room. Additionally, it is used automatically as a side-attack to chip away at the bulwark beast's armour if using a melee weapon.
Players can bind this tool regardless of their Mining level. If they do not have the required Mining level, then the pickaxe temporarily acts as the pickaxe of the highest usable tier. For this reason, it is often requested from smiths as a way to quickly tool up.