Cleaning Copper Pennies

Too much can go wrong with cleaning, therefore NEVER clean anything you value. However, you can always try out your experiment on common copper pennies from circulation. I'd be interested in seeing before and after pics of that.

I just use straight vinegar 4% or 5% depending on what I have for those that msut be cleaned. like the ones I have right nor I just cannot read, either from being filthy or verdigris. One is a wheat and after about a hour in vinegar I was able to read 192_ S. Still some green on it blocking the final bit of the date, but I have it in some lime juice right now to see if there is any hope on finding out what it is. If it hadn't been for the vinegar I wouldnt have even known it was a wheat! so much gren and grime on it.

this is the only time I bother with cleaning a coin to b able to tell what it is. sad as it is my first 20's S cents so it would have been a hole filler if not in such bad shape so it will likely go into a tiny jewelry bag until something comes along to fill the hole instead.

Just use a 10 grit sanding disk, it will be a lot faster.

i do it to find out what it is. is it a zincoln or a copper LMC? found out mine was a very worn and corroded 1921 S. too bad shape to fill a hole, but I put it in the paint pile and may liven it back up with the paint so it can be seen as a 1921 again without a microscope.

So I must collect coins based on your or some one else's criteria? Sorry I was under the false impression my collection was MY choice what to keep and why. So in MY collection, a grime covered verdigris covered coin that cannot even be told if it IS a coin gets cleaned so features can be seen and possibly even a date.

a 1921 S cleaned is still a 1921 S in MY collection. Better to have a cleaned identifiable 1921 S than just a grimy corroded green metal disk.

Extra virgin, that sweet oil stuff, or what? does the olive oil remove the verdigris?

First, I didn't know you were talking about dug coins so I take back the post I didn't make.

Olive oil won't stop verdigris. I *do* like the stuff as a cleaning agent in the right situation, though, especially heavily-encrusted coins. I soaked an IHC for a full year, once. It was barely readable before (no pics), but here's the "after:"





The whole coin was originally that black, and most of it had a thickness dimension. Not it's just a patina.