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Cleaning corroded pennies and coins


Q. I'm a parent, working for a small booster club. A local mall has generously donated money from their wishing well. There are a lot of coins and the money nice but the only way the bank will take it is to have it cleaned up. The water has corroded and pitted the pennies (silver coins were easy to clean). My question is, if there is a something that divers use to clean corrosion off copper- like pennies? We have tried all the science fair type of solutions, but there are bags of pennies. Is there a way to remove the corrosion and save the penny. One mother is using a very strong bathroom cleaner that is for removing rust deposits from sinks. If you leave the pennies longer than 30 seconds they go black.

Mrs. Yaple
parent - Lewisville, Texas


When the mint needed to change pennies from solid copper to copper plated zinc in 1982 because of inflation, the durability of pennies sitting in a wishing well could not be at the top of their priorities. The pennies corrode horrendously and it's not always a simple matter of washing or cleaning them if they have become seriously disfigured by corrosion. Hopefully someone will have a helpful suggestion, but visit the US Mint website -- maybe they have a program to give credit for unusable pennies?

Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey


A. This information still came up on google. It was helpful and led me to the us mint website, where I found out this (direct quote from
"Mutilated Coins: United States Coins no longer fit for circulation are classified as "uncurrent" or mutilated.

Uncurrent coins are coins that are worn yet recognizable as to genuineness and denomination, and are machine countable. Uncurrent coins are redeemed by the Federal Reserve Banks, then forwarded to the Mint for disposition.

Mutilated coins are coins that are chipped, fused and not machine countable. Mutilated coins are only redeemable through the United States Philadelphia Mint facility.

All uncurrent or mutilated coins received by the Mint are melted and reused in the manufacture of coinage strips."

So, in the original situation, possibly sending the corroded pennies to the PA mint for redemption may be your easiest bet.

Dawn Hoff
- Yorktown, Virginia


A. Possibly- a small tumbler with a plastic media- Might work.

James Watts
- Navarre, Florida


A. There is a product available called, curiously, Penny Brite [linked by editor to product info at Amazon] Cleaner/Polish that does a good job on copper & copper based alloys (brass, bronze). Unfortunately Ted is correct about the current copper plated zinc pennies. Maybe you should campaign for the U.S. Mint to take this junk back at face (?) value.

Ray B Anderson
retired metallurgical engineer - Kent, Ohio

Rock Tumbler


I'm not sure if this is totally applicable, but I was watching a show related to soda and it's effectiveness in cleaning pennies. Apparently, soda (or cola, pop) is really good at getting off all the "tarnish". Just a thought.

Good luck!

- Wheeling, Illinois


A. A dry tumble in walnut shell will more than likely get most of any "wishing well wish residual" (sorry, I couldn't resist) off. After that, try a mixture of Muriatic Acid [linked by editor to product info at Amazon] in a warm water bath. I don't see you needing any more than 10% acid to the solution.

Russell Ackerknecht
- Greenwood Lake, New York


A. Try ammonium citrate- mixture of citric acid and ammonia(25%)-5% solution is good(dissolve 50 gms citric acid in 1 lit water,add ammonia to pH 9). If this looks complicated 5% citric acid also must work.

Goran Budija
- Zagreb, Croatia


Q. I have corroded pennies that have excessive scale and deposits built up on them. They were removed from a drain line after about a year of submersion. Some are melded together - too bad to even attempt clean up. But most of the others could probably be salvaged if I could come up with a good cleaning solution for severe corrosion and concretion build up.
I will try a 5% and 10% solution of Muriatic acid, both with and without salt as an additive and post the results soon.

Roy [last name deleted for privacy by Editor]
- Warrington, Florida USA


Hi, Roy. Pennies since 1982 are made of zinc, which I believe will dissolve rapidly in muriatic acid. I think it won't succeed and may be dangerous, but good luck.

Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey


A. Ted,

The suggestion is sound and not theoretical, I assure you. I've been using this process for years and the pennies will not degrade in any way shape or form.


Russell Ackerknecht
- Greenwood Lake, New York, U.S.A.

February 10, 2008

A. You can clean pennies in ordinary ketchup. Just empty a bottle into a large bowl and dump in the pennies. Give them a stir and wait a bit. Bright and shiny in no time.

Kathleen Benedick
- Baltimore, Maryland, USA

April 27, 2008

thumbsup2I just tried using ketchup to clean pennies and found it worked quite well.

Rusty Morris
- Half Moon Bay, California

February 26, 2008

Q. I tried cleaning old wheat pennies with vinegar and salt and the pennies turned a dull pink in color. Is there any way to restore the pennies, or at least make them shiny again?

Micah Glover
student - Birmingham, Alabama

February 26, 2008

Vinegar and salt is mild on people but exceptionally aggressive on copper and brass, Micah. Try a commercial copper cleaner instead. A mild one like Brasso [linked by editor to product info at Amazon] will restore the warm color of the penny soon if not immediately.

Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey

March 3, 2008

Q. We received over 70 pounds of corroded pennies for the Pennies for Peace project. Anyone have an easy way to clean that many?

Richard M. Dailey
- Huntsville, Alabama

April 29, 2008

Q. We have a number of coins that were exposed to salt water in Hurricane Katrina. Some of them are silver that we had bought as investments (silver dimes/dollars), some we had "left over change" from trips overseas many years ago, but none necessarily valuable.
I would like to know how to clean them. Some have a bright aqua coloration; some (an Eisenhower dollar, for instance) look like they have rust on them. Can you give me some suggestions, please? I have already tried baking soda and a toothbrush. Thank you.

Sharon Demetz
- Upland, California, USA

June 24, 2008 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. I have been given a few thousand pennies that are very tarnished from a fountain in a mall. they were given to us for a veterans memorial to clean and cash in. Can you tell me what will clean them PLEASE!

Tom Wilkins
hobbyist - Hot Springs, Arkansas

August 1, 2011

A. Go to They are a company that cleans, counts and banks fountain coins for you for a small percentage [Ed. note: 25% of the recovered amount]. Saw them on "Modern Marvels", "coin op" episode.

Gary Uhlan
- New Haven, Connecticut

December 14, 2014

They clean bulk coins bulk coins with no numismatic value.

[anonymous] <= was submitted with a probably fictitious name
- Texas USA

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