Chunks of barronite were an item that could be received when obtaining barronite shards (at a rate of 1/20), or a guaranteed loot from crushing barronite deposits in the Ruins of Camdozaal. To be eligible to receive them, players must have talked to Sir Pear Visor in the centre of the Old School Museum beneath the Falador Party Room, and have agreed to help him. After agreeing to help him, a message appeared in the player's chatbox stating: You have enabled additional drops from activities across the game. To disable these speak to Sir Pear Visor in the Falador museum.
The item was given to Sir Pear Visor as part of the community goals for global contributions toward the Old School Museum expansion; the 'Check-Progress' option on the item will open the museum expansion's contributions interface. Upon the goal being reached, the item became unobtainable.
