Mullock refers to the worthless rock and dirt removed to reach a profitable seam or excavated while sinking a shaft. Unlike tailings, which are the leftovers after ore processing, this material never goes to the mill. It is typically dumped in large piles on the surface or used as backfill in empty underground stopes.
Heard on the job
The night shift spent twelve hours shifting mullock just to get back to the main vein.
Insider tip
In Australian mining slang, someone who talks nonsense is sometimes said to be poking mullock.
Also heard as
- deads
- attle
Do not mix it up with
- Tailings: Mullock is excavated waste rock that never goes to the mill; tailings are the crushed leftovers from ore processing.