Borrowed from German Nickel, first used in a text by the Swedish mineralogist Axel F. Cronstedt as an abbreviation of Kupfernickel (“a mineral containing copper and nickel”), from Kupfer (“copper”) + Nickel (“insignificant person, goblin”), originally nickname of Nikolaus (“Nicholas”), due to the deceptive silver colour of the relatively valueless ore. Compare cobalt as related to kobolds.