Industrious like a brownie, Blue-cap was said to have enormous strength and was capable of toiling long hours. He was visible as a blue flame that floated about the shafts, moving whatever objects the flame settled on.
Blue-cap's wages were left in a corner of the mine every two weeks. If they were below what he felt he deserved, the spirit indignantly rejected the sum. If the wages were above what he felt he earned, he left the excess amount.