Author Topic: Uncleaning a coin  (Read 3463 times)

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Offline mrbadexample

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Uncleaning a coin
« on: October 28, 2017, 01:43:34 PM »
Hello all.

I have this Jersey 1/13 shilling. It is, to me, an attractive piece in all aspects except for the fact it has been horribly cleaned and is a nasty pink colour.

I don't know if there's a better way, but in a bid to return it to a natural state I want to wear the cleaned surface away. I would prefer a lower grade, uncleaned coin. To this end I will be carrying it in my pocket with the rest of my change for the foreseeable future.

I have no idea how long this might take.  :-\

I would appreciate any better suggestions!
Cheers,
MBE


Offline bruce61813

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Re: Uncleaning a coin
« Reply #1 on: October 28, 2017, 03:40:48 PM »
Don't try to wear-away the surface, that will really ruin it. If you have a window sill that gets sun, just place it there. Flip it over every couple of days. Alternately, if you have a gas oven with a pilot light, just place the coin on non-metallic dish or tray and let the coin sit in the oven. No heat needed, but again flip the coin to expose both sides evenly. It may take as long as a month. Scrub the coin with a nylon type brush under water with some soap, if you think the coin has been waxed.

Bruce

Offline mrbadexample

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Re: Uncleaning a coin
« Reply #2 on: October 28, 2017, 04:21:39 PM »
Thanks Bruce. It's not waxed.

I perhaps didn't choose my words very well - I don't really want to deliberately wear away the surface as such, more treat the coin as it would have been treated whilst in circulation - handled, kept in a pocket with other items etc so the wear would be "natural".

Sunniest window I've got is the greenhouse. I could leave it in there?

Same for this horror?

Offline FosseWay

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Re: Uncleaning a coin
« Reply #3 on: October 28, 2017, 06:40:02 PM »
I conducted an experiment into wear over the last couple of years. I kept a bog-standard circulated (probably a good VF to begin with) 1 krona coin - the old Cu-Ni kind - in my coat pocket for about 18 months. It jangled around with keys and other junk and regularly got wet and frozen. I also made a point of handling it - rubbing it between thumb and forefinger - while waiting for the bus, walking along etc.

Net result: virtually nothing. What mint lustre it still had at the start it lost, but no real change in the wear of the design was visible. It just goes to show the sheer amount of use needed to achieve the kind of wear that you often see on bun pennies.

Offline bruce61813

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Re: Uncleaning a coin
« Reply #4 on: October 28, 2017, 07:58:27 PM »
Cu-Ni would not change noticeably, but a copper-based coin will react with the atmospheric gasses and the UV in sunlight. It is a slow oxidation process, but not glacial  ;D.  The greenhouse should work, just don't fertilize it...
bruce

Offline andyg

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Re: Uncleaning a coin
« Reply #5 on: October 28, 2017, 09:13:53 PM »
Cu-Ni would not change noticeably, but a copper-based coin will react with the atmospheric gasses and the UV in sunlight. It is a slow oxidation process, but not glacial  ;D.  The greenhouse should work, just don't fertilize it...
bruce

Here is my unfortunate recent purchase - question - how best to remove the polish?
always willing to trade modern UK coins for modern coins from elsewhere....

Offline mrbadexample

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Re: Uncleaning a coin
« Reply #6 on: October 28, 2017, 11:16:23 PM »
I'd be tempted to try a bit of acetone on that Andy. Is that a Siberian 10 kopecks?

Offline bruce61813

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Re: Uncleaning a coin
« Reply #7 on: October 29, 2017, 01:47:17 AM »
I agree, acetone, and then some isopropyl alcohol. Any residue can be removed by using soap and water.

Bruce

Offline andyg

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Re: Uncleaning a coin
« Reply #8 on: October 29, 2017, 09:25:16 AM »
I'd be tempted to try a bit of acetone on that Andy. Is that a Siberian 10 kopecks?

It's a five kopeks that if I'd known it had been polished I'd not have bought.

Thanks both for the suggestions - will give it a try...
always willing to trade modern UK coins for modern coins from elsewhere....

Offline capnbirdseye

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Re: Uncleaning a coin
« Reply #9 on: October 29, 2017, 09:54:09 AM »
Expose the coin to Sulphur just overnight, I have experimented with yellow sulphur you get from garden shops,  either drop the coin in the powder overnight or for a more delicate tone put some powder in jar of water & shake it up & suspend the coin in it, I use one of those green nets off birdfood fatballs.  This treatment works on copper & silver.

 I take the view that if your coin has been chemically cleaned then it can equally be chemically restored !
Vic

Offline mrbadexample

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Re: Uncleaning a coin
« Reply #10 on: October 29, 2017, 01:50:42 PM »
Are you in a position to be able to show us the results Vic?

Offline capnbirdseye

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Re: Uncleaning a coin
« Reply #11 on: October 29, 2017, 02:10:19 PM »
Are you in a position to be able to show us the results Vic?

I'm sure I've posted lots of coins that I've treated this way although mostly silver that has been chemically cleaned but I don't have before & after photo's to compare,
 I can show you an example of how Sulphur will tone a coin on this coin which was burned & I  removed most of the charred residue but it left the coin looking 'cleaned' so I treated it with sulphur


All you need to do is test it on a low value coin if your not confident
Vic

Offline capnbirdseye

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Re: Uncleaning a coin
« Reply #12 on: October 29, 2017, 02:34:20 PM »
Here's an Akbar Dam that I got in a mixed lot, it's obviously been cleaned by someone but I've just put it in sulphur powder to see if it improves & will post the results later.
Vic

Offline capnbirdseye

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Re: Uncleaning a coin
« Reply #13 on: October 29, 2017, 06:42:28 PM »
Here is that same coin after just 4 hours in sulphur, it looks like a natural tone & far better than before


lower photo is after a light rub

Vic

Offline mrbadexample

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Re: Uncleaning a coin
« Reply #14 on: October 29, 2017, 08:28:21 PM »
That's impressively quick, Vic.  :)