Ever Destroy A Coin To Learn How It Reacts?

I admit I've succumbed to the destructive urge - once I scraped down a zinc penny until the zinc was showing all around the rim, then put it in vinegar. This ate away the zinc but not the copper, I was hoping to get a very thin but still recognizably penny-like piece of copper foil. Unfortunately it didn't perfectly work out.

Hey scottk, with modern coinage, it may react differently than some of the old silver coins, but I still like the idea of your experiment. Have you considered getting a number of quarters and doing a different thing to each so you can see how each reacts to your various tests, independently. If you really want to get scientific, you could look up "Design of Experiments" and it will help you set it up so that you'll know the individual effects of the tests, but also the results of their interactions on the coins.

So long as you don't completely destroy the coins, to the point they're too bent or crumbling, you can always throw them into a roll and take 'em to a bank. Let them be the bank's problem. Ever needed a little copper for a chemical reaction? I have. Messed up a good number of older LMC coppers...took them to a bank I never go to when I was finished. No money wasted.

If you're going to experiment, use modern-day stuff. Unless you want to experiment with silver, in which case buy the "worse than cull" grade stuff (i.e., coins bent in half, massive holes, details obliterated, etc.) that sell for next to melt anyway. The coins are a step away from the melting pot as it is, so if you completely destroy it, no real harm done.

I obtained a counter marked coin. It had obviously been heated to apply the countermark. I had a debate with some other collectors as to which side the heat was applied. Most said the burn't looking side was the one that had the heat applied. I actually thought it might be possible it was the other side( no oxygen) To settle the discussion I took an old silver coin and applied a blow torch to it. It was really interesting. My suspicion was right the side opposite to the flame ended up looking burnt...but even more intriguing was the migration of copper to the surface of the coin.

Initially it looked like copper plate then with more heat it took on a burnt hue

No, I've never destroyed a coin to see how it would react.

However, I have been playing around with chemicals trying to stop zinc rot. It is not going well. My results so far: The corrosion is mostly gone and the cent turns pinkish.

I've had similar results with copper cents.

I'm probably/most likely wasting my time but I studied experimental design for two years in college and I really can't stop myself. LOL

There isn't really a "delayed reaction" for silver; the main reason to avoid tap water for silver is to avoid the dissolved salts in tap water precipitating out on the coin when the water dries. But there is a worrying "delayed reaction" for copper: tap water has been shown to catalyse the formation and progression of aggressive verdigris, or bronze disease.

As for the philosophical question: if we're talking about a coin that's already environmentally damaged, or a coin rescued from the melting pot, then I don't think anyone has any problems using it for science. A coin pulled from circulation is a slightly different matter - a coin might be common and mundane today, but just remember that in a hundred years time, the future owners of your experiments might be cursing your bones for what you did to "their" otherwise attractive coin.

The potential value of a coin should be your guide as to what level of respect you need to adhere to, when deciding to clean it or not clean it.
Most ancient ancient coins have been cleaned at some stage or other, almost always to their benefit, but there always risks involved; experience is essential, best left to the professionals.

For mine, a common date silver dollar in VG condition is 'open slather' to any method you may wish to clean it. It is safe to assume that it will loose very little value, if any at all.
I would probably just clean such a coin using plain old soap 'n water with my fingers, under a running faucet. I have to admit, I have cleaned quite a few coins in this way, and I can't see that I have caused any further damage, even decades down the track after cleaning.

For other than ancient coins*, where cleaning presents even the tiniest of threats to decrease the value, don't clean them!
Plain old common sense should apply.

*see above.

Nevertheless, you can have lots of fun experimenting with coins. That includes heat treatments, chemicals and plating.
Perhaps you could even learn something! For example, I have learned how to not burn by fingers, using heat treatment!.

If Mint employees can have a bit of fun and tomfoolery with coins, why can't we?
Lots of examples of fun with coins have been reported here on the CCF. For instance, how about Araditing a quarter to the footpath, or parking a car on top of a five dollar note?