Like cobalt, nickel bears a name drawn from mining superstition. The ore Cronstedt studied was called Kupfernickel by German miners, meaning copper-nickel or, more pointedly, Old Nick's copper, Nick being a name for the Devil. The miners cursed the mineral because it had the reddish look of copper ore yet stubbornly refused to yield any copper, and they held a malicious spirit responsible. When Cronstedt proved that a genuine new metal, not the Devil, was the hidden ingredient, he kept the second half of the miners' epithet as its name. Nickel and cobalt together are the periodic table's memorial to the goblins and devils that pre-modern miners believed lurked in the deceptive ores of the deep workings.
Nickel has a mundane but widespread modern legacy: it is the most common cause of metal contact allergy in humans, provoking itchy rashes from cheap jewellery, watch backs, belt buckles and coins in a significant share of the population, especially women, who statistically show higher rates of nickel-related skin sensitisation. The European Union's Nickel Directive, in force since 1994, restricts the amount of nickel that can leach from items in prolonged skin contact, a regulatory response to a problem that traces back to the same reactive, faintly ore-mimicking metal the old miners once blamed on a devil in the rock.