Is there something that can be mistaken for PVC residue?

smprfi

Anyone?

coinguy1

smprfi,

Can you provide some more information? Was that an "official" determination made by a major grading company as a reson for no-grading a coin? Or, do you think you see PVC on a coin but are not certain?

TomB

I would expect that some people might think verdigris, which is corrosion of copper and can be bright green, might be PVC. Also, I have PCGS bag Lexington commems for PVC when these commems were taken by me out of their original wooden boxes. The pine that the coins were stored in toned many of them in green and auburn shades that PCGS graders have evidently never seen and are clueless about. However, they have slabbed all of them once I told them what they were looking at. Good thing I send them in for the experts, huh?

smprfi

Mark I got back a 1918-s SLQ from pcgs that says pvc residue.I don't see any thing.

coinguy1

smprfi,

I thought, from the way you had posed the question, that was probably the case. "PVC residue", to me, is different from "PVC damage," which would not be treatable.

I would suggest, that if you work with a local dealer, you see if he will remove (what I will presume is) some light PVC for you. An alternative would be for you to try it yourself, but I'm very hesitant to recommend that if you are not familiar with the process.

Finally, if you go to coin shows, you might use that as an opportinity to show the coin to a few dealers who might be able to give you some opinions / help.

smprfi

Would an ascetone dip remove the residue?

coinguy1

smprfi, P.M. sent.

Conder101

Sure, mold slip. In the manufacture of many plastics (including the mylar they make saf-flips out of.) they have a problem with the hot plastic sticking to molds, transport rollers etc. To prevent this they apply a light coating of oil called mold slip to them. usually the manufactures try to keep the amount of oil to a minimum and they often try to wash it off of the plastics as well. Sometimes they aren't successful. If a coin get placed in a product that still has the mold slip on it it can be transfered to the coin. If the grading service sees an oil ayer on the coin it gets rejected because it COULD be the plasticizer used in PVC flips and if it is even if no damage has occured it still may in the future. Rather than taking samples and running a chemical analysis to determine what the oil is they just BB it for PVC contaminaton. Rinse it with acetone to remove the oil and send it back.