PVC on mint set coins

[jrh-migration]

I recently sent in a 1962 mint set for authentication and grading to NGC. I realize the coins aren't really worth that much, but my reasons for doing so were not related to the coins value. At any rate, the coins were in the original packaging and I cut them out and slide them gently (without touching) into non-PVC flips and sent them to NGC.

 

To my surprise three of the ten coins were returned with no grade and the notation PVC ? How can this be I called NGC and was not able to get an explanation (they were very nice on the phone). I don't doubt what they said (I'm a novice), but how did this happen? The two nickels and one dime had the PVC designation and the other seven coins graded MS-64 to MS-66.

 

Does the original packaging from 1962 contain PVC and if so why were only three of the ten coins affected? Is there some other explanation? Is this a common occurrence?

 

 

[PQSeated]

I have some mint sets that have coins in them with PVC on them. I'm not sure how it got started on them, but it sure makes them look terrible. I also have some mint sets that have coins that are starting to tone slightly.

[GDJMSP]

While I cannot say with certainty - because I have not knowingly ever seen one myself - there are counterfeit Mint sets. As most know - the envelopes are a breeze to counterfeit. And I have heard from a few who work at packaging manufacturers of the same type of pliofilm packages as the Mint uses being ordered.

 

So it would be quite possible for coins that were previously stored in PVC flips to be used in such manufactured sets. That is the only explanation I can think of for this to happen.

[gmarguli]

Most likely the coins developed a white haze to them which is somewhat common. NGC bagged these as PVC even if it isn't actual PVC, but some other surface contaminate.

 

Across the street I had some dimes (60s & 70s) I cut from mint packaging bagged as PVC.

[cladking]

I've looked at a lot of mint sets and watch for signs of counterfeiting. While I have seen some repro envelopes and packaging, I've never seen a mint set package which I believe was counterfeit. There are pre 1959 and '66/'67 sets with coins switched but not counterfeits. For the main part there is no incentive to fabricate these sets. The coins of which they are composed will cost more than the sets themselves to say nothing of the costs and time to make them.

 

This is something to be on the lookout for, but don't expect to find them.

[jrh-migration]

Thanks for the responses. I realize I'm the only one who knows for SURE that the coins were handled so carefully. They were, in fact, never touched and they were, indeed, taken straight from original packaging a placed in non-PVC flips (and sent the same day to NGC).

 

There would seem to be no reason to counterfeit such inexpensive coins (or packaging) and I know for a fact they were not mishandled.

 

At any rate, it gives cause to wonder (at least for the non-expert) about this "grading game" when something like this can happen even with a first rate third-party grader like NGC (perhaps the best third-party grader). How can three of ten seemingly "pristine from the mint" coins be judged to have PVC contamination?

 

I still have not had any luck with my question about whether or not the original mint packaging could have contained PVC ? Does anyone know ?

[GDJMSP]

Pliofilm - the packaging material the Mint used for many years is made from rubber hydrochloride. It is 90% natural rubber that has been treated with hydrochloric acid & chlorine to produce the material. As such - I do not believe it contains any PVC.

[Oldtrader3]

I wonder if the "white residue" in these early '60's mint sets is Zinc Stearate, commonly used (during that period) as a release agent in plastic processing to prevent hot plastic film or molded parts from sticking to metal tooling? Zinc Stearates would typically turn white when they precipitate out of the barrier matrix.

 

I am on a fishing expedition at this point and have no proof, but suggest that this may be a starting point to investigate film extrusion release agents that the Mint's film suppliers used during that period. The Mint's film supplier would have that information.

 

Revised later: Natural Latex has many long amino acid chains, many additives including (sometimes) Human Urea and Formeldehyde. This is why there is such a giant human allergenic problem with Latex. If Pliofilm is Latex based, who knows what could be causing the problem. Without some scientific testing, it is moot. However, I have observed that aged medical grade latex forms a white oxide barrier coating on the surface over time. Probably because talcum or Zinc Stearate are used as release agents.