So how does one know whether a particular plastic holder is PVC or not? Well, one old test is to hold a copper wire to the flip and expose both to a flame. Old-time collections still come onto the market in such albums, and they’re not a pretty sight. The damage to the products’ reputation, however, was irreversible, and the company went out of business. Collectors should never use PVC products for long term storage, a fact which became abundantly clear when a particular brand of coin album had to replace this plastic in its product line with another, less harmful one about 20 years ago. If a coin hasn’t sold after a few months, the dealer should place it in a fresh flip, but this doesn’t always happen.
Using PVC coin holders is perfectly all right for short term storage and display. Any coin displaying such green, oily film on its surfaces may be submitted to Numismatic Conservation Services, LLC (NCS) for removal of the contaminant. In its earlier stages, however, PVC film is removable with proper conservation. Prolonged exposure to PVC deposits in the presence of moisture can actually lead to the formation of hydrochloric acid which permanently scars the coin. Over time, this can settle onto a coin and deposit an oily film-that sickly, green slime that leaves an outline of the coin on the flip and adheres to the high points of the coin itself. After that time the chemical softening agent that gives PVC its great flexibility may start to leach out. Where the problem lies is that such storage is suitable only for the short term, say, less than six months. In fact, using this plastic for coin flips is OK, too. In most of these applications PVC’s qualities are completely benign. PVC is short for polyvinyl chloride, a popular and widely used plastic that has countless industrial applications. You, my friend, have experienced a PVC moment. Some flexing of the soft flip is enough to make the coin break free, and then you see it-that pale green outline of the coin imprinted on the inside of the flip. When he or she hands you the flip, it seems that the coin is actually stuck to the inside of it.
You’re at a coin show or a dealer’s shop when you ask to see a coin that’s in a flip, one of those double-pocket, plastic envelopes that so many dealers use to display uncertified coins.
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