Johnson mines

Welcome to Johnson mines,
we have the longest shafts,
to not enjoy your time you'd have to be daft,
we just know you'll immediately want to mine
when you get a closer look at our thick veins!
Always more to see, and with a stroke of luck,
you'll be going down and never get stuck.
Down deep is where we thrive,
erecting wood to ensure we survive.
Grab an axe and pick a shaft,
and get ready to master the craft,
great balls of gold await.