A vertical slot or groove cut into the side of a coal seam or rock face. It provides a second free surface for the material to break toward when blasted or wedged, drastically reducing the force needed to extract the block. In historic hand-mining operations, hewers would undercut the seam first, then make this side cut before wedging the coal down.
Heard on the job
Finish the holing across the bottom, then start the nicking on the left rib so we can drop this block.
Insider tip
Historic hand-miners considered this one of the most physically demanding tasks, as it required swinging a pick sideways in tight quarters.
Also heard as
- shearing
- Nickings