A mineral lode exhibits this behavior when the fracture or shear zone tightens up, causing the ore shoot to thin out or disappear entirely. Miners tracking a rich vein might find the walls closing in until only a barren seam of gangue or a tight fracture remains. It forces geologists to decide whether to keep driving the tunnel in hopes the vein widens again.
Heard on the job
The quartz leader started to wring about ten meters past the fault, leaving us with nothing but barren country rock.
Also heard as
- pinch out
Do not mix it up with
- Nip-out: A nip-out usually refers to a coal seam disappearing due to a geological anomaly, whereas wring usually applies to hardrock mineral veins narrowing.