Copper. Slang for a police officer. A coin. That metal pans and wires are made of.
What’s so mysterious? A lot.
Copper is a catalyst. It’s variable oxidation states and low coordination numbers allow it to do funky things, bonding and unbonding with whatever floats its way.
Copper is used in whisky stills, partly because it’s malleable and conducts the heat through the whisky really well, and partly because it seems to affect the flavour. One story, related to me by Ben from The Whisky Shop, was the story of Old Pulteney whisky, back in the days when the distillery was first setting up, the days when they decided to make the most important feature of the distillery – the still. It was made offsite and transported carefully to the distillery in the Highlands of Scotland, where they tried to take it into the building – but couldn’t. The manufacturers, so the story tells, had made a mistake and ordered a still too tall for the distillery. Still, never mind, they said, and they lopped off the top, making a low, squat-looking still pot that led to shorter
refluxes, forever after blamed for the “dirty” flavour of the Old Pulteney spirit.