Brewer's: Fairy of the Mine
A malevolent being supposed to live in mines, busying itself with cutting ore, turning the windlass, etc., and yet effecting nothing. (See Gnome.)
No goblin, or swart fairy of the mine, Hath hurtful power o'er true virginity.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894