Anyone know how to remove PVC from Copper
Coin Finder
Posts: 7,240 ✭✭✭✭✭
Two small spots on the reverse of a lincoln cent Proof
0
Comments
<< <i>There are three things which will work acetone, acetone, and acetone. >>
It should not hurt the surface but the PVC may have already hurt it if it had long enough.
Pure acetone works best.
Awww, aint that a cute lil way to be rude.
<< <i>Two small spots on the reverse of a lincoln cent Proof >>
Question: You state 2 small spots. Thats not usually how people describe pvc since it usually covers one or both entire sides of a coin. If you can post a photo we can be sure to help diagnose & describe how to fix it. If youre sure its pvc read below.
Acetone is ok.
BUT
for lincoln proofs & modern copper nickel proofs nothing I have found beats CLOUDY ammonia. Dip rinse & send to slabland. Doesnt touch natural toning but eats pvc & haze well. Works better than anything I have found for haze on modern proofs.
WARNING
This stuff is pretty nasty smelling and getting tough to find. Use chemical gloves & rubber tongs if possible (and if you value the skin on your hands). Do not use without a good exhaust fan and NO your bathroom fan does not count. Do it outside if you have to. The last jug I bought I had to go to several small grocers in seedy neighborhoods to find. Not sure why. The cloudy part may be some sort of detergent mixed in it but it doesnt leave pink like dishwashing detergent, doesnt touch the natural reds . "little bo peep" brand is the one I use. The only time I've had it change a coins color is on pvc covered copper from an old harco album and it turned the technicolor that acetone causes on the really damaged stuff also. This stuff just has less of a tendency to cause the technicolor effect then acetone on pvc copper.
<< <i>Well I cannot photograph it well enough, spots are small like half a bb but it is raised, hard crud and it is green. I tried pure acetone, then blue ribbon, it really did not do anything but make the green lumps less green. A few might have come off.... small lumps that is.... I do not believe the crud has eaten into the surface...... >>
Thought it might be that. Its not actually pvc. Its whats commonly reffered to by ancient collectors as bronze disease. Its actually if I remember right copper sulfide? That green stuff is very hard to remove properly if not impossible in some cases. Try soaking the coin indistilled water for long periods and that should pull some of it off (the water will turn green). I use a waterlogged toothpick on ancients, but on a proof coin thats not going to cut it.
After the distilled water and it dries I only know of one method that leaves the natural patina and its not nice. Some others here may have a better one. I have a small supply of typewriter correction fluid from the 60's or 70's (think its carbontetrachloride). It's clear, dries instantly and kills that green stuff. Only problem is its super carcinogenic and impossible to find since its been banned commercially for a heck of a long time.
Hmm, interesting advice about the old typewriter correction fluid. I had forgotten about that stuff. I learned about using that stuff on old classic coins from some very famous numismatics in Cleveland back in 1971. I remember using that stuff when I was in College and stopped using it when I ran out of it.
That stuff really worked. I would like to find more of that stuff.
Now this thing about the cloudy ammonia. Also very interesting. Little Bo Peep is the brand? Is it still made?
I would like to hear more about this. I do not even recall what kind of ammonia we have in our stores today.
Thanks for your informative posts. I am most impressed.
<< <i>shottaker:
Hmm, interesting advice about the old typewriter correction fluid. I had forgotten about that stuff. I learned about using that stuff on old classic coins from some very famous numismatics in Cleveland back in 1971. I remember using that stuff when I was in College and stopped using it when I ran out of it.
That stuff really worked. I would like to find more of that stuff.
Now this thing about the cloudy ammonia. Also very interesting. Little Bo Peep is the brand? Is it still made?
I would like to hear more about this. I do not even recall what kind of ammonia we have in our stores today.
Thanks for your informative posts. I am most impressed. >>
Little bo peep is the brand I have found here in Michigan. Regular ammonia doesnt seem to work near as well. It's labelled cloudy ammonia, but I have not tried another brand. It does kill haze on proofs quite well and works on silver proofs as well. It doesnt leave anything thats detrimental that I can tell as I've owned several that I used this on for over 10 years. One thing it is particularly good at is that orange gunk that sometimes gets on modern proofs, usually when someone overuses a can of jeweluster and it gets that film on every coin dipped after that.
Are you the same oreville that used to be very active on the Ebay forums years ago? I used to lurk there and rarely posted but saw your posts quite often. They were always insightful and it contained a lot of old time knowledge that very few people know.
The last place I found the correction fluid was when an old print shop auctioned off their equipment. I have found some in garage sales from time to time. Almost out and pretty soon may have to resort to smuggling some in from Mexico.
But I did find an Material Data Safety Sheet from Church & Dwight Inc that listed both Parsons and Bo Peep on the same sheet which leads me to believe they are the same. I suspect that they made both brands but have now consolidated to Parson's only. Parson's is made in Clear, Lemon, Pine, and sudsy varieties. I think the right one to use would be sudsy as the Bo Peep was described as cloudy/sudsy.
Hope that helps.
“In matters of style, swim with the current; in matters of principle, stand like a rock." - Thomas Jefferson
My digital cameo album 1950-64 Cameos - take a look!
Yes. The same old oreville. Sometimes I used the oreville21 user name over there as I can't seem to find my password for oreville on ebay. Note to self. Call ebay for resetting password.
I still peek in on the ebay board about once a month.
<< <i>Thanks so much, I guess I should have said it is a matte proof Lincoln. Anyone have any cloudy amonia or old correction fluid?
You dont need the ammonia for a matte. The stuff you have (hard green) needs the correction fluid method since the ammonia wont touch that stuff. There may be other ways to get it off.
The distilled water may help to diffuse it, but you will need to use acetone or clean distilled water when you pull it out of the water after rinsing. This is due to the distilled water pulling some of the green. It will then be in the water and if you dont rinse it well afterwards in clean distilled water or use acetone as a diffuser you will notice a thin layer of green all over the coin! It will then grow over a period of time into more corrosion. That green stuff used to be considered the kiss of death to a coin.
In the case of a matte proof this is a fairly pricey coin that I might consult someone in person at a major regional show. There are some guys who are great fixit guys you might be able to get to do the coin under your supervision or get more advice from. Make sure you ask around at many tables to make sure you find "the Man" and not some idiot with a can of jewelluster. Its one thing to play with a $20 1991-S lincoln proof and quite another to play with a matte. Different animal entirely. If youre worried about the spots spreading in the meantime I would ask about light machine oils as a stopgap measure. They take the oxygen away and stop the reaction. The oil will have to be removed before it will holder and theres only some types that should be used.
I might actually consult NCS about this coin over the phone as they may have a way to fix it. Some of their work sucks, and some is wonderful. I think it would just be a matter of expressing that you need 2 spots killed without changing the color of the rest of the coins patina. They should be able to tell you if they can do it.
We will try to help as much as we can, but without seeing the coin via photo or in person its tough.
<< <i>There are three things which will work acetone, acetone, and acetone. >>
YEP!
The Penny Lady®
Bronze Disease
Call NCS or find some old time copper experts at a show. Your coin is a pretty nice coin and using sodium bicarbonate will ruin it.
This coin really needs a picture for even a rudimentary prognosis since it can be fairly easy or very difficult to fix.
<< <i>
<< <i>There are three things which will work acetone, acetone, and acetone. >>
YEP! >>
read the posts further. Its not pvc.
Bronze disease sadly
<< <i> spots are small like half a bb but it is raised, hard crud and it is green. >>
If it is hemispherical and raised like half a BB, there will be damage beneath. The hard green verdigris you see
is made of copper compounds ,deriving the copper portion of the compunds from the coin. Raised verdigris will generally leave more
underlying damage than a flat spot of it. I use Verdigone for such coins, as it does not affect the surrounding
patina nearly to the extent of other substances that would remove the verdigris. I know some have expressed
concerns on this new product, but IF one feels they MUST remove verdigris, this would be my first choice by far.
Jim
<< <i>
<< <i> spots are small like half a bb but it is raised, hard crud and it is green. >>
If it is hemispherical and raised like half a BB, there will be damage beneath. The hard green verdigris you see
is made of copper compounds ,deriving the copper portion of the compunds from the coin. Raised verdigris will generally leave more
underlying damage than a flat spot of it. I use Verdigone for such coins, as it does not affect the surrounding
patina nearly to the extent of other substances that would remove the verdigris. I know some have expressed
concerns on this new product, but IF one feels they MUST remove verdigris, this would be my first choice by far.
Jim >>
Welcome to the boards Jim, and thanks for the plug.
Hi Jack,
Thanks for the welcome! I really don't feel it is a plug as I used it soon after
Thad invented it and I remember how much flak was thrown on the other boards
at first
But IF I needed to remove verdigris from a copper coin, it is what I would use. One
problem that is mentioned here is that many do not differentiate verdigris ( bronze disease)
from PVC attachment/damage or "carbon spots" which is not it's use.
Hope you feel better! I didn't make it to the SD show either.
Jim