PVC Question

[JRRRR]

I'm new to the forums, and an amateur collector. I just read the NGC January 2008 eNewsletter on PVC and began to wonder about the way I have been protecting some of my loose coins.

 

I have some of these coins sealed in Foodsaver vacuum bags, using the Foodsaver vacuum machine. I also have a few in Black & Decker bags as well. I have looked at the box that the bags came, but did not find any information on what the bags are made of. I do not have the Black & Decker box because I only use that brand once in a while.

 

I have also been searching the forums and reading the various threads on PVC but cannot find any reference to the Foodsaver vacuum bags or process. I know that because I am no longer sure that these bags do not contain PVC, I should remove the coins; however, at the current time I have no other safe container to put them in.

 

I have looked at each and do not see any visible signs of green or any other color problems. Has anyone looked into this before?

[Conder101]

I hope the NGC people don't mind me answering this.

 

PVC is seldom used for food products. It is approved for some wrapping films but I don't believe it is approved for long term storage products. One way to tell for sure is what is called the Bielstein test.

 

Take a piece of copper wire and remove th insulation from about two inches of one end. Heat that in a gas flame until the flame burns cleanly. (This is to remove any traces of insulation and other contaminates from the copper.) Touch the hot wire to the plastic to be tested so that a little of the plastic melts and sticks to the wire. Put the wire and plastic back into the flame. If it burns with a green flame then the plastic contains PVC.

[JRRRR]

Thank you for taking the time to reply. I will try the test. If there are any other thoughts on the issue from anyone else, your advice is welcomed.

 

SE New Mexico

[ant]

thanks conder great info!

[Oldtrader3]

Sometimes food wrap materials are PVDC or Saran wrap. At higher temperatures and over time, PVDC can release Vinyl Chloride which is the same substance which also is leached from PVC and will damage coins.

[farmboy-migration]

PVC (Poly Vinyl Chloride) will outgas even in temperatures as low as 98.6 degrees F. Rigid (hard) inert acrylic would be your best option to store your coins. Hard plastics, particurlarly acrylic, do not contain plasticizers which promote the outgassing of chloride and other harmful gasses. Just a thought for you to consider.

[Smilie Puss]

Ok Condor

 

The test you mentioned can give a false positive especially if the copper begins to melt or has been contact with a sulfates or nitrates in addition to the chloride decomposition products from PVC. Oxidation of copper and copper salts at elevated temperatures will produce the charasteristic green emission @324 lamda in the visable spectrum.

 

Usually PVC is a soft plastic and using ridged plastic slips may be a better guide than doing emission spectrographic analysis to test for PVC. I would prefer IR analysis instead. But then who has an IR instrument available?

 

The best option is to order slips from PCGS or better yet grab a supply the next coin show where PCGS people taking submissions.

 

The best way I have found to store coins is in Intercept Shield albums that have a high tech polymer application developed by Lucent Technology that absorb oxidizing gases like hydrogen disulfide, etc. and protect coins. Also the plastic slide windows are ridged plastic and will protect against hand oil/salts. Storage can be on a book shelf and looks like your well read. Besides what thief steals books or objects that look like books?

 

Food for thought?

 

itsnow24u

[Conder101]

Your typical gas flame such as on a stove will not get the copper hot enough to melt, and as for the copper salts and oxidation, that is why you first heat the wire until it burns clean, to burn off those contaminates so that you are only testing the plastic itself.

 

Sure quality lab equipment will give you even better results from better tests, but as you say, who has them.

[BadThad]

Your typical gas flame such as on a stove will not get the copper hot enough to melt, and as for the copper salts and oxidation, that is why you first heat the wire until it burns clean, to burn off those contaminates so that you are only testing the plastic itself.

 

Sure quality lab equipment will give you even better results from better tests, but as you say, who has them.

 

I do!

[HiHoAudio]

For the non scientists reading this thread there is a simple rule of thumb to tell whether a clear plastic coin flip is PVC or Mylar. If it's soft and you can bend it a dozen times without it breaking it's PVC and should not be used.

 

If it's brittle and breaks in half after a dozen bends it's usually Mylar, which is safe for coins of all types.

 

I use Saf-flips, which are Mylar, and I can recommend them highly. Though why they didn't just call them Safe-flips is the question.

 

Did they run out of "E"s?

[Conder101]

Because by making it a non-standard spelling they can copyright and/or trademark the name.

[HiHoAudio]

Because by making it a non-standard spelling they can copyright and/or trademark the name.

 

That makes sense.

[M.H.-migration]

I had a simular question so what I did was call the manufacturer that made the clear plastic wrap, baggies etc. The clear plastic wrap is microwave safe and when I called and asked about their products they said none contain PVC. I used the clear plastic rap on my uncirculated cent rolls and then put them in a zip lock bag. Before I sealed the bag completely, I took a straw and sucked as much air out of the baggie as possible and the quickly sealed the bag. I'll know in about 20 years if that worked or not but it's logically seems better that doing nothing. I think you are onthe right track...

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Kevondo-migration]

Is there a simple "At Home" (or something I could do at a show) test to detect "PVC" contamination of coins? I'm just about done sending raw coins to TPGer's and them coming back "Enviormental Damgae" . NCS is a great solution. Also I don't buy RAW coins from dealers or on Ebay. I'm getting to be a "SLABS ONLY" guy.

[BadThad]

If the surface debris is green, it's verdigris which is either caused by the degradation of PVC or exposure to air and moisture. Posting pictures helps determine the exact nature of the corrosion. If PVC is suspected, a simple rinse in distilled water (to neutralize the acid) followed by acetone will usually remove it. If it's normal coin verdigris, it is best conserved by specialty removal products like VERDI-CARE™.

 

Good Luck!

[Jim Beam]

"For the non scientists reading this thread there is a simple rule of thumb to tell whether a clear plastic coin flip is PVC or Mylar. If it's soft and you can bend it a dozen times without it breaking it's PVC and should not be used.

 

If it's brittle and breaks in half after a dozen bends it's usually Mylar, which is safe for coins of all types."

 

OK - I just purchased 100 2.5x2.5 inch cardboard coin flips. They were advertised as "cardboard/Mylar". The plastic is soft, I can bend it and it will not break. Short of having forensic testing done on these, would you risk storing your Morgans (mostly MS - some XF-AU) in these? I have purchased silver dollars from members of these forums and they arrived in the same holder type I just purchased. Do you use them for the long term or are these just holders you use for the short term? I reaIize using Saflips would be the best way to go and probably over the long run the safest bet. I, and I am sure others, would appreciate your thoughts, past experiences, and knowledge related to these "soft" coin holders. Oh, one more question - it was stated in another post on this thread that if there is "green" residue on a coin, it is verdigris. What does PVC on a coin surface (what color) actually look like? Thanks.

[Virtually_Here-migration]

some place on the box is a recycling symbol

 

1 inside a triangle is PET or PETE (polyethylene terephthalate)

 

2 is HDPE high density polyethylene

 

3 is PVC

[noow]

Jim- the 2.5x2.5 coin flips you have are COMPLETELY SAFE. It is a common misconception that mylar is always brittle. I use the exact same holders and I guarantee they have no pvc whatsoever.

 

SIMPLE PVC TEST

 

Smell it. If it smells strongly of plastic, oil, or smells like a fume, it is either PVC or something else you don't want your coins in. Cardboard/plastic holders generaly do not contain PVC. (They should have a cardboard scent)

 

PVC looks like a green slime coating the surface of the coin. This slime will slowly eat away the surface of the coin (you probably already knew that).

 

Long term storage is just fine, if you don't mind a bit of toning

 

They usually take 20 years to tone in a C/P holder.

 

Saflips are good too, but more brittle.

 

Hope this helps

 

 

 

-19