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 Replies: 13 / Views: 5,630 |
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Pillar of the Community
United States
718 Posts |
Do the holders used by PCGS and NGC protect silver coins from toning, or further toning? Anyone have a personal experience?
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Pillar of the Community
United States
2023 Posts |
The seal is not perfect -- toning can still happen if the slab is not stored properly.
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Pillar of the Community
United States
4469 Posts |
Some holders will tone the coin. A Morgan in a NGC Fatty holder will often show edge toning.
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Rest in Peace
United States
17900 Posts |
Both PCGS and NGC have gone through phases where their slabs caused problems that were not there before encapsulation. The worst was the long years of ASE proofs that had white milk spots and haze. So not only will the encapsulation not always protect from toning, in some odd cases it will cause toning, or haze, or spots. Usually if you are purchasing a coin that has been encapsulated for more than 5 years without showing any degradation's, then you are probably safe for anything to crop up later. Keep the coins out of long exposures to the sun, which is most unlikely most of the time, anyway. |
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CCF Advertiser
United States
1533 Posts |
They are not air tight. I am currently engaged in a red cent stability study in a variety of slabs.
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Pillar of the Community
 United States
718 Posts |
Alpha2814, what constitutes "proper storage?" Hermetically sealed in a mayonnaise jar left on my back porch (If I had a back porch.)? I have my slabbed coins in a velvet lined wooden box from the folks at Lighthouse that I keep in my closet (away from my dirty socks). I live in Southern California so I'm not down wind from an active volcano either.
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Moderator
 United States
188001 Posts |
Proper storage means in an stable environment: low humidity, no large temperature swings, no pollution, etc.
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Valued Member
United States
404 Posts |
My 2 cents:
PCGS secure slabs are supposed to be more stable than most;
Older PCI slabs make purple and red toning, rather dramatically;
NCS states that milk spots are uncleanable and the result of a mint process (believed to be the result of a chemical left on the planchets after they are cleaned)
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Bedrock of the Community
13014 Posts |
Quote:The worst was the long years of ASE proofs that had white milk spots and haze. Milk spots are an issue with the mint not a holder issue. Raw coins were getting them just as much |
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Moderator
United States
188001 Posts |
Quote:
Milk spots are an issue with the mint not a holder issue. Raw coins were getting them just as much I agree. |
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Pillar of the Community
United States
6383 Posts |
For copper and silver coins especially it is worth storing them with desiccant. This helps prevent any toning that might be promoted by humidity. I use silica gel packs in my home safe and my safe deposit box. I recharge them every few months by baking them in my oven for 3 hours at 300 degrees F. They last indefinitely and are a good investment.
Toning will not be a problem for stabbed gold (or platinum) coins.
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Pillar of the Community
Canada
1747 Posts |
The RCM also has the same issues with Milk spots on some of their Bullion coins as well. The consensus here is that in the minting process the chemicals were not completely removed before the strike. |
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Pillar of the Community
United States
1499 Posts |
The short answer is, "No,' but it slows it down IF the coin has been dipped with dip residue left on it. In those cases the coin can tone very quickly. That also goes for "red copper" that has been made so by chemical means.
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Valued Member
United States
127 Posts |
Correct storage will lessen any discolorations. If you keep your coins in a safe, make sure you open the safe from time to time and let it air out. I have seen collections left in a closed safe for 10 or more years. The humidity in a closed safe causes problems. Never keep coins (slabbed or otherwise) in an attic or basement.
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Replies: 13 / Views: 5,630 |
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Posted 03/07/2017 3:11 pm
