Preventing "greening" of old copper coins

[TrpnBils]

I dug an IH penny the other day and it had no green on it that I could see when it was dug. I took it home and rinsed it off with water (no chemicals), and as soon as it dried, it turned very green. Is there any way to prevent that? I know this isn't the answer, but I keep thinking back to iron relics I've run through electrolysis to knock the rust off of and then preserved in a thin coat of beeswax to prevent future rust. Anything like that that can prevent the green? It's not in fantastic shape or anything and certainly isn't worth more than a couple of bucks, so I'm not super worried about destroying a rare piece of numismatic history or anything, I'd just like to have it look like a copper coin again!

 

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[since1984]

personal opinion; certainly be cleaned
respects.

 

[since1984]

personal opinion; certainly should not be cleaned
respects.

 

[cudamark]

Why not? If it isn't worth anything numismatically, make it look the way you want. Electrolysis or a peroxide bath to remove the "green" and then some CoinCare to coat the coin and prevent it's return.

 

[jeff of pa]

one thing you need to Be aware of.

there is a 50/50 chance the Green toning is the reason you can see the detail on it.
once you clean it, it may look like a copper slug.

again... Just be aware

 

[TrpnBils]

I've read that before, but what makes me wonder is the fact that I didn't see any of that green until I rinsed it. Prior to that I wiped the mud off well enough to identify it and date it, but unless the green was magically just underneath the parts I didn't rub clean, I don't really know why it was that quick of a change. Any ideas?

 

[huntsman53]

Next time, try a light bath in dishwashing liquid and water mix, rinse, pat dry between the folds of a soft towel, then coat it with Extra Virgin Olive Oil or Mineral Oil. You want to remove any contaminants from the coin including salt and oil from your' skin, then protect it from any further damage with the Olive Oil or Mineral Oil.


Frank

 

[Silver Searcher]

The only water you should have be using is distilled, tap water created the reaction.

SS

 

[cudamark]

If it did, it wouldn't be any water I'd want to drink!

 

[jeff of pa]

I've read that before, but what makes me wonder is the fact that I didn't see any of that green until I rinsed it. Prior to that I wiped the mud off well enough to identify it and date it, but unless the green was magically just underneath the parts I didn't rub clean, I don't really know why it was that quick of a change. Any ideas?

Yes was probably just a crust over the Green.
I've seen this with Indian Head cents often.

The green actually made them appealing imo