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PVC Residue or Organic Material Reaction with Acetone
appletree
Posts: 15 ✭
Will either PVC residue or an organic material react on a silver or gold surface with acetone to produce a haze or a waxy looking substance?
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Soak in acetone to loosen the material. Repeat in virgin batch and rinse with deionized water. If haze appears repeat process. If haze remains then the surface has been compromised. PCGS and NGC offer restoration processes that may remove the haze.
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What kind of container are we talking about? Glass? Styrofoam? Polypropylene?
I believe a glass container for acetone with a screw on lid to prevent evaporation would be the optimal choice for something other than a quick dip. No Styrofoam as it will melt. Don't have a clue about polypropylene.
Proper rinse technique would be alcohol followed by DI water.... Cheers, RickO
Contaminated acetone could definitely leave a residue on gold or silver... the acetone should be changed if the coin is really cruddy and the last immersion should be in totally clean acetone... and the acetone should be of lab quality.
Proper rinse technique would be alcohol followed by DI water.... Cheers, RickO
Thank you for the guidance. Yes, all in glass containers. I knew about the acetone followed by dH20, didn't know about the alcohol rinse. I'm not sure what the waxy haze is. It is very disconcerting. Under the assumption acetone would not react with an inert metals.
Repeat and see what happens.
??
Isn't there a possible reaction between acetone and copper? I kind of remember somebody saying that. Since silver and copper coins are alloyed, and contain copper, there could be some possibility of a reaction with those coins.
I was told copper will react with acetone depending on the copper planchet preparation. Some early Lincoln cent proof planchets were prepared with harsh acidic rinses. The metal remains vulnerable to a surface reaction with acetone. Never with alloyed gold or silver. Hindsight, shouldn't have messed with the coin. Expensive lesson.
Thank you.
I have never used water after acetone, is there a consensus in this
I rinse it off quickly, my theory is that anything removed by the acetone could remain in suspension. At the rate acetone evaporates, any suspended matter would remain high and dry on the surface of your coin.
An acetone bath is one of the safest and most effective ways to remove surface contamination,to include PVC,on a coin.
As for acetone melting adhesive material,many a glued on "s" has fallen to the bottom of the beaker after the 1909 S V.D.B. hopeful has spent a little time in acetone.
Great spirits have always encountered violent opposition from mediocre minds.-Albert Einstein
Soft plastic roll tubes (from mint) can leave black on ASE coin edges. This can result in return from buyers. Guy in coin club had this happen then had to dip and scrub edge of them all then the roll sold no problem. Perhaps storage in a hard plastic tube may be better.
Any ideas to help? Thanks to anyone who replies...
Sounds like the sort of thing I'd send to PCGS for restoration. It's likely it will be returned in its original OGH, declining conservation. But I'd trust PCGS and their experience.
Lance.
Isn't there a possible reaction between acetone and copper? I kind of remember somebody saying that. Since silver and copper coins are alloyed, and contain copper, there could be some possibility of a reaction with those coins.
I was told copper will react with acetone depending on the copper planchet preparation. Some early Lincoln cent proof planchets were prepared with harsh acidic rinses. The metal remains vulnerable to a surface reaction with acetone. Never with alloyed gold or silver. Hindsight, shouldn't have messed with the coin. Expensive lesson.
Thank you.
Acetone will not harm metal. Copper included.
But, acetone will react with surface contaminants. And that can change the appearance of some copper pieces, even those that have not circulated but have been exposed to contaminants in the air, let's say.
Acetone may also give a coin a "dried-out" look after dissolving and removing all surface oils. A little coin conditioner can help restore a more natural look (Blue Ribbon, CoinCare, e.g.) but experience is valuable so you might experiment with coins with little value first.
Lance.
Thank you for your informative reply. I remember reading something similar elsewhere but figured it wouldn't hurt to see if anyone had further experience. Copper is notorious for getting those carbon spots and while I'm not 100% certain, these look more like carbon than anything else. Your advice sounds like a best alternative and if PCGS won't touch it then I should probably just learn to live with it. I appreciate your helpful advice.
I've tried to learn to live with it but I am never able to overlook it. Experienced collectors and dealers are quick to see them and say "no thank you". As I get better replacements I sell, usually taking a loss, and chalk it up to tuition.
Lance.