Do Cardboard 2x2's still have PVC? I think so

Hello. I was taking out my Indian head cents from cardboard holders I put them in a few years ago. I am putting them now in a Dansco. They looked dark and dirty so I rolled a qtip with acetone over them. To my amazement, all of them gave off blue and/or light green verdigris on the qtip. I would never put them in there like that, so I'm afraid it's the holders. My local shop sells these holders, 100 for three dollars, and I also get them at the long beach coin show. I can't tell the difference between them, and the ones I buy online are the same. I read another online forum and someone said its hard to find any info on these holders and most dealers don't even know what they are exactly made of. This person also said Mylar windows are clear when you look through them, PVC ones are murky. Others have said older holders may have PVC but most modern ones don't. What do you think? I have thousands of coins, mostly world coins, in these holders. Is it just these older IHCs that had verdigris already and worsened inside, or should I worry about all my coins?

 

Log in or Sign up to hide this ad.

/1/ It is NOT the PVC, it is the plasticizer (softener). Since companies frequently change their products, it's not always the same, especially for no-name or house brands.

At least 2x2 are cheap enough you can move to:

/2/ There are simple tests for plastic type. http://www.boedeker.com/burntest.htm

 

Verdigris is not the same as the "green slime" associated with PVC damage.

https://en.wikipedia.org/wiki/Verdigris

Chris

 

I've taken out coins from old world coin sets where the holders were soft and most would say have PVC. I would see light blue color on my qtip. The verdigris link shows a picture of some copper/brass underground metal with bright blue corrosion all over. Looks like the same color on my qtip

 

regular 2X2 have mylar.

 

Verdigris and PVC slime are two different things. The tests for plastic type above are good, but overly complicated. If you want to test, try this...heat a copper wire in a flame till it is hot, touch the plastic you want to test so that it melts on the copper, return the copper to the flame. Polyester (Mylar), polyethylene, polypropylene will burn clean, PVC will have a green flame.

 

Some of the old ( 20 yrs or so) ones had some pvc windows, but they tore too easily and they were replace by the mylar types of plastic, so I don't suspect that from modern 2x2 as much as staple holes. They penetrate from the outside through the mylar and environmental gases and moisture have access to your coins, but it is the same as all coin holders, storage beyond the holder must also be considered.
Also stainless steel staples should be used in the 2X2, as regular steel staples reacts rather quickly if moisture is high.

 

I read badthad's comment in a similar post and he said PVC can lead to verdigris, and they are virtually the same thing some times.

 

The cardboard holders shouldn't have any PVC or plasticizers in them... if anything, you might be dealing with cardboard dust, which can lead to problems, since the pulp is acidic.

As for "Plasticizer free PVC" that I see advertised on eBay. I don't think that it's possible, for one, but even if it is, that doesn't change the fact that PVC is still PVC... vinyl chloride. I can't imagine flips being made that have zero plasticizer but are PVC, as they'd be extremely brittle due to the rigidity of PVC at room temperature without plasticizers.

 

Sounds like you need to improve your storage methods, highly unlikely that's PVC plasticizer residue, sounds like plain old verdigris developing on your coins.

 

Are you sure you read his comment correctly?

Chris

 

Since the coin chemicals involved are almost identical , verdigris and PVC damage initiate from different chemical reactions similar to NT vs. AT toning. Verdigris and natural toning are processes from chemical reactions with the environmental conditions usually over a long or very long period of time. PVC damage ( "slime") and AT are initiated by exposing the coin metal to chemical or other artificial treatment to get coin toning over a short or very short period of time.

 

This is not a case of the 2X2 holders at all! Its the atmosphere. IMO.

Just about all raw copper alloys will develop a "film" over time. Go look at a leather purse with brass fittings that your wife has not used in years. Just about 100% of the time there will be the usual crud build-up where the brass meets the leather. Just leaving a copper cent in a desk drawer will produce the film - eventually.

 

PVC shouldn't damage coins. It's likely where they were placed.

 

Of course, I can read. PVC plasticizer is a residue containing hydrochloric acid, therefore, it induces the formation of copper chloride....which is a verdigris salt. In this case, the coins were not exposed to PVC as they were stored in mylar 2x2's.

 

I was directing that question to the OP! He said........you said........in another thread.

What's the matter? Can't you read? Just kidding!

Chris

 

Bingo. Copper is reactive. when it reacts with things in the air it forms copper compounds. Most copper compounds are green or blu-green. when the acetone and white cotton swab are used on the copper coin some of the copper compounds get picked up by the white cotton and a green or blu-green color is seen. Has nothing to do with PVC or PVC plasticizer residue. Just natural copper oxidation. I haven't seen a 2X2 with a PVC film window in over forty years, and they were old 2X2's then.

 

Lucky! I see them every day and 2% have rusty staples while 60% have a residue circle (color dependent on the coin's alloy) on the plastic window!

 

I have ruined hundreds of wheaties with this type of holder..

 

You'll often see that on 2X2's with mylar windows as well because the coin was contaminated when it went INTO the 2X2.