I gave bad information above. Coalface workers there were called Strippers (yes, I know) or Getters. The men who reworked the tunnels were Rippers.

What many people don't realise is that the tunnels in deep underground coal mines don't stay open, but close in in all directions. What starts out as a 8'x 8' tunnel supported by formed arch RSJs/I-Beams becomes a tiny hole full of twisted girders. The Rippers re-cut the tunnel, removing the steelwork and sending it to the pit bank, where blacksmiths straighten it out for re-use.
The Rippers are supplied with the so-called 'rings' in some areas by teams of lads who sledge the girders up the Jig (haulage) or tunnel to them. Hence Jig-runners and Ring-draggers. Been there, done that.

No-one would try to reopen a closed deep coalmine. There isn't a mine down there any longer. You'd have to start from scratch.

If the bottles David descibes above are Dudleys, then our bottles weren't. Ours were enamelled, rectangular with a kidney-shaped cross-section. And a narrow neck with a cork.