Cleaning Copper Coins With Calgon??......

Garrett424

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Jun 20, 2014
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I posted a thread in the coin forum asking this same question.

I recently found my 1st large US cent which I'm excited about; but it's pretty toasted. I can't even read a date and can only make out just a few characters on either side.
I did the hot peroxide treatment, soaked it in distilled water for about 30 hours and it's been soaking in olive oil since then. I did the same to an old 1863 Civil War store token I found the same night and I'm definitely beginning to see some improvement in that one. But, it's probably not as old as the LC.

First Large Cent & Old Token Last Hours of Summer 2014 003.JPG reverse First Large Cent & Old Token Last Hours of Summer 2014 004.JPG

I read on a professional coin cleaning site that they sometimes use Calgon to clean badly rusted copper coins. The idea is to use the toothpick method and dip the toothpick in the Calgon and a very low concentration of water.
It's supposed to change the surface tension of the water and loosen the dirt, rust and crud more easily, the same way detergent does only supposedly better. Calgon is basically a water softener according to what I have read thus far.

I'm wondering if anyone here has either heard of or even used this method; and if so, how well did it work and what kind of results did you get?? I'm curious if it's worth running out and buying Calgon if regular detergent will produce almost the same results.

The Calgon is also supposed to harm any patina if used in too strong a concentration or if allowed to make contact with the coin for too long, which leads me to believe it may be worth a try. I'm assuming that this is why they recommend dipping the toothpick in it rather than soaking or washing the coins with it.

Not knowing the date yet, I would like to find out if at all possible. If I was to be so lucky as to have found a key date, I sure wouldn't want to ruin it before I even get started. Not that I'm expecting that but then again, you just never know......

Thanks in advance.
 

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Frankn

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Well from looking at that coin I would say you are ready for the last resort!
This method is only for use as a last resort. Use rubber gloves and eye protection. Have a jar full of water ready. Get some muratic acid and wet a clouth 'dampen it' with the acid. wipe the coin with the cloth for about one minute, then drop it in the water. Examine it and dry it. repeat as necessary.
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I will get flack from the coin people, but it does work.
 

RobRieman

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Nov 12, 2012
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Key date or not, if it's that toasted the only value would be to the finder of the coin. I would use any method you can come up with to attempt to find a date just to satisfy your curiosity but don't worry about ruining the value. Good luck!
 

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Garrett424

Garrett424

Silver Member
Jun 20, 2014
3,164
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Granite, Maryland
Detector(s) used
Teknetics Omega 8000
Teknetics Delta 4000,
Deteknix XPointer,
Fiskar's Big Grip Digger & my old Army Trench shovel for the tough jobs
Primary Interest:
Metal Detecting
Key date or not, if it's that toasted the only value would be to the finder of the coin. I would use any method you can come up with to attempt to find a date just to satisfy your curiosity but don't worry about ruining the value. Good luck!


I'm assuming that this particular coin has no value to ruin.
As you mentioned, my goal is to satisfy my curiosity without destroying whatever may remain of any date.
 

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