Do You Clean Your Raw Coins Before Storing Them?

Ouch, and yikes!

My seven year-old grandson knows I'm into coins and one day he explained how he and his mates had this neat way of cleaning any old copper one and Two Cents they might find.

In his words... "We just put them in a jam jar, ruinate on them, and in a week they're back looking like new!".

Ah kids... don'cha sometimes just wish you were still one?

And looked up ruinate in the dictionary and got this: 'ruinate' pronounced ruin-ate. A sure-fire way of ruin-ing anything remotely good.

In case you're wondering, his name is Connor and he wears a cheeky grin. Just be sure not to leave him or his mates alone anywhere near your "dirty old" coins.

Just the plane fare

Actually, I consider that there are two stages of "cleaning", one gentle non-altering one I call "conserving" (from ancient coin terminology) and "cleaning".
Conserving consists of removing surface gunk that obscures details (it's actually not uncommon to find older coins with a layer of dirt/dust/nicotine cemented on)and then the oils from handling. I fail to see how leaving a coin crusted with gunk is somehow going to increase it's value.
"Cleaning", on the other hand, actually alters the physical surface of the coin (dipping, polish, whizzing, etc) and does alter the value of the coin-and rightly so.