Is this corrosion, pvc, or something else?

Aspie_Rocco

Three different coins with similar green on the surface. Is this PVC? Corrosion? Or something else?
Anonymous poll.

RobertScotLover

That is verdigris, and its crystalized so not spreading ie its dried out, happens a lot on silver. When its that small of an amount it doesn't affect grades in the least. I have many that are hollered and even stickered.

dsessom

Coin boogers. Sometimes, acetone will remove it.

ricko

Whether verdigris or PVC, an acetone bath will rectify the problem. If that does not work, it must be 'something else' Cheers, RickO

Cougar1978

Whatever - needs be removed if u want any chance sell it.

PerryHall

@ricko said:
Whether verdigris or PVC, an acetone bath will rectify the problem. If that does not work, it must be 'something else' Cheers, RickO

Is acetone safe on copper? I wouldn't hesitate to use it on silver or gold but I've read that it can discolor copper.

GaCoinGuy

Acetone and a rose thorn.

dsessom

@PerryHall said:

@ricko said:
Whether verdigris or PVC, an acetone bath will rectify the problem. If that does not work, it must be 'something else' Cheers, RickO

Is acetone safe on copper? I wouldn't hesitate to use it on silver or gold but I've read that it can discolor copper.

Acetone CAN discolor copper if left in a bath for hours. You also need to rinse it with distilled water afterward and dry it by dabbing (not wiping) with soft cotton, or you can use a blow drier.

Alternatively, this works very well on copper and will not discolor it: https://www.amazon.com/Unbranded-Coin-Care-Cleaner/dp/B002CN78OE

ricko

@PerryHall ... The only time I have seen a discoloration on copper, is when there was unknown substance(s) (unknown to me) on the cents surface. Then the copper turned a light pink. I have put it on 'new' cents with no effect. Cheers, RickO

Aspie_Rocco

Thank you for the replies everyone.

Is this something that develops/grows/appears after grading and or CAC review?

Will it get worse over time?

These photos came from 3 different 1913 Buffalo nickels. One is on eBay presently, one was an ms65 CAC which I returned when I saw the green, another was an amazing ms64 toner I got and sent back last week.

Up until reading the responses posted here, I thought this was a form of PVC, and told the sellers I returned the coin to that I thought it was pvc.

I see now I was likely mistaken in my assessments, but I still don’t like that green stuff on any pcgs graded coins.

I had a similar green blob in a graded Franklin proof last year. Coupled with the recent finds my level of scrutiny is at an all time high when buying.

Sapyx

Corrosion.

The patch in the first/fourth picture (between the E and D) shows evidence of corrosion that has been previously treated. See the dark brown "moonscape" staining or cratering surrounding the green patch? I suspect that all used to be green as well, and that someone (a long time ago) has used alkaline chemicals (ammonia, caustic soda or similar) to remove a patch of corrosion.

The green spot in the centre was either too deep and stubborn for the chemical to remove, or the corrosion has reformed there since the treatment was applied.

Acetone removes PVC goo, but has zero affect on ordinary corrosion.

For cupronickel coins like Buffalo nickels, corrosion like this is not "contagious" - once in a slab or holder, it should not spread any further.

For a silver coin like a Franklin, they don't tend to form green corrosion nodules like this unless they get placed in a particularly nasty environment (like getting stored in a drawer with a bunch of leaky batteries). A "green blob" on a Franklin is more likely to be PVC.

mark_dak

@Sapyx said:
Corrosion.

The patch in the first/fourth picture (between the E and D) shows evidence of corrosion that has been previously treated. See the dark brown "moonscape" staining or cratering surrounding the green patch? I suspect that all used to be green as well, and that someone (a long time ago) has used alkaline chemicals (ammonia, caustic soda or similar) to remove a patch of corrosion.

The green spot in the centre was either too deep and stubborn for the chemical to remove, or the corrosion has reformed there since the treatment was applied.

Acetone removes PVC goo, but has zero affect on ordinary corrosion.

For cupronickel coins like Buffalo nickels, corrosion like this is not "contagious" - once in a slab or holder, it should not spread any further.

For a silver coin like a Franklin, they don't tend to form green corrosion nodules like this unless they get placed in a particularly nasty environment (like getting stored in a drawer with a bunch of leaky batteries). A "green blob" on a Franklin is more likely to be PVC.

I was kind of surprised at some of the other answers. I'm not an expert but as you say there is a good amount of "moonscape" as you call it that suggests to be there is/was some corrosion there. The green spots seem to be in several spots where the metal appears to have been eaten away and noticeably lower than surrounding metal. I am a bit surprised that one of the coins ended up with a bean.

Mark

lkeigwin

Acetone can remove PVC. It is ineffective on verdigris.

Acetone does not change the color of copper or any other metal. It reacts with organic material. The sometimes perceived change to copper color is the result of the removal of environmental contaminants from the copper coin’s surface. Substances acquired from circulation.

Soak an uncirculated red cent in acetone for days. Its color will remain unchanged.
Lance.

lkenefic

Not to split hairs, but isn't PVC damage a form of corrosion? I voted PVC, but in my experience PVC looks a little darker green... and acetone definitely works to remove it and stabilize the coin.

PerryHall

@lkeigwin said:
Acetone can remove PVC. It is ineffective on verdigris.

Acetone does not change the color of copper or any other metal. It reacts with organic material. The sometimes perceived change to copper color is the result of the removal of environmental contaminants from the copper coin’s surface. Substances acquired from circulation.

Soak an uncirculated red cent in acetone for days. Its color will remain unchanged.
Lance.

What happens when you take an older circulated cent with natural brown color and soak it in acetone for several days? Do you think it will straight grade at any of the major grading services?

Goldbully

Just today I dipped a toned 1830 CBH in acetone that had a tiny amount of what looked like PVC damage(blue green crud) for 10 minutes. Then I took a wooden toothpick and carefully removed the stuff...it was like a dream come true. I've never done this before. Then I used a cotton swab to dab up the particles and voila, gone with no telltale signs anything was removed or had ever been there. I then dipped the coin in a bath of distilled water for a few minutes. Took the coin out put on a soft cotton cloth and patted dry. Wish I had a before picture now.

edited to add: after pic.

lkeigwin

@PerryHall said:

@lkeigwin said:
Acetone can remove PVC. It is ineffective on verdigris.

Acetone does not change the color of copper or any other metal. It reacts with organic material. The sometimes perceived change to copper color is the result of the removal of environmental contaminants from the copper coin’s surface. Substances acquired from circulation.

Soak an uncirculated red cent in acetone for days. Its color will remain unchanged.
Lance.

What happens when you take an older circulated cent with natural brown color and soak it in acetone for several days? Do you think it will straight grade at any of the major grading services?

I wouldn't hazard a guess about TPG grading. Conserved coins can reveal problems hidden by years of toning.

I'm just saying that acetone won't change the coin's surfaces. It can look different when all the surface oils and other contaminants are removed.
Lance.

DisneyFan

@lkenefic said:
Not to split hairs, but isn't PVC damage a form of corrosion? I voted PVC, but in my experience PVC looks a little darker green... and acetone definitely works to remove it and stabilize the coin.

Can PVC also be a haze area on the coin?

telephoto1

First two coins...Corrosion, also known as verdigris. PVC damage usually starts on high areas from direct contact with the offending vinyl, not deep in the crevices as shown here...and doesn't make little crusty globs like this. Bottom image isn't focused well enough to make a determination.