Author Topic: White haze on Proof silver coins  (Read 3946 times)

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Offline Alan Glasser

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White haze on Proof silver coins
« on: February 21, 2011, 04:57:26 PM »
Good morning all.

I have a beautiful proof silver crown that has turned hazy prior to my purchasing it. (I think they call it "milky surfaces".) Is there a way to restore the original proof surface without damaging the coin. Also, another proof silver piece has a nice tarnished fingerprint on it. Any suggestions. I have tried acetone (be very careful if you use acetone...VERY combustable) but the results weren't great. Any ideas?

Thanks.    Alan (he who NEVER cleans a coin)

Offline Figleaf

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Re: White haze on Proof silver coins
« Reply #1 on: February 22, 2011, 12:03:38 AM »
Here's a recipe that will deal with the milky surfaces:

  • cover coin with sodium bicarbonate (leavening agent, NaHCO3)
  • Sprinkle carefully with lemon juice, the two substances react chemically (bubbles)
  • Rinse in lukewarm water
  • Dry thoroughly, carefully wipe off remaining toning

Fingerprints are acid burnt into the metal. They cannot be removed without removing silver.

Peter
« Last Edit: February 22, 2011, 10:39:40 AM by Figleaf »
An unidentified coin is a piece of metal. An identified coin is a piece of history.

Offline Alan Glasser

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Re: White haze on Proof silver coins
« Reply #2 on: February 22, 2011, 01:34:06 AM »
Thanks, Peter.

I'm going to give it a try. Regarding fingerprints, I always thought that they were caused by oils on the skin. I didn't realize it was acidic.

How DO you learn all this stuff??

Alan

Offline Prosit

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Re: White haze on Proof silver coins
« Reply #3 on: February 22, 2011, 01:37:17 AM »
Almost all oil is acidic at least to a very small amount.

Dale

Thanks, Peter.

I'm going to give it a try. Regarding fingerprints, I always thought that they were caused by oils on the skin. I didn't realize it was acidic.

How DO you learn all this stuff??

Alan

Offline Alan Glasser

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Re: White haze on Proof silver coins
« Reply #4 on: February 22, 2011, 01:55:48 AM »
Good to know...Thanks!!  Alan

Austrokiwi

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Re: White haze on Proof silver coins
« Reply #5 on: February 22, 2011, 07:25:35 AM »
Regarding the finger prints.  Try using a Polivit plate  It may reverse a little of the damage. The plate is  a sheet of sacrificial metal  you disolve household soda in warm water  put the plate in the water submerge the coin ensuring at least part of it is touching the plate..... bubbles should start appearing on the plate as soon as the coin touchs it........ Not recommended for old toned coins.......it reverses the oxidation completely (in a few seconds)