PVC & Vedigris?

TheGoonies1985

Can you transfer PVC after says working around your home and touching PVC plastic with your hands then handle coins? Or doe sit has to comes in direct contact with the coin? If you wash your hands with soap after then touch coins I would assume all would be OK (drying hands afterword as well)? I am not a science guy when it comes to this stuff hence my question.

Been wondering this for a while with my OCD.

TheGoonies1985

I would imagine copper coins would be easier to get PVC versus silver and gold coins? Are nitrile gloves safe to use with when dealing with touching coins and when using acetone?

Mr_Spud

Nitrile gloves should be fine. You won’t transfer PVC contamination to other coins unless you touch some of the gooey green slime that builds up sometimes. But sweat on your fingers is more than enough to cause a latent fingerprint to show up over time that permanently etches coins. This is one of the main reasons I like to give a quick acetone bath to just about every raw coin I get. Especially if I’m going to put the coin in an album. If the album tones the coin over time, latent fingerprints can show up and lower the eye appeal. For these raw coins that I use acetone on, if nothing is visible on the coin and you don’t suspect PVC, then I tend to not do second rinses and I use the same acetone for more than one coin. Like I’ll put new coins aside until I have a bunch and do them all at the same time.

But like you learned with your sticky coin, do at least one or more rinses with fresh acetone if you see gunk or suspect PVC and don’t re-use the acetone for other coins

jmlanzaf

You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

TheGoonies1985

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

What about when working with black electrical tape and the glue on that?

OAKSTAR

Just to clarify for me.. Are we saying PVC and verdigris are the something here?

TheGoonies1985

@OAKSTAR said:
Just to clarify for me.. Are we saying PVC and verdigris is the something here?

None of my coins ever had verdigris. I would not buy a coin that had visible verdigris. A few of my coins had some PVC. But I bathe all my coins as mentioned. Does acetone take of verdigris on silver coins?

OAKSTAR

I'm confused between PVC and verdigris. I need pictures.

TheGoonies1985

@OAKSTAR said:
I'm confused between PVC and verdigris. I need pictures.

Vedrigis is that crusty green like sand. PVC is just like toning. That is the way I see it anyways. Maybe I am wrong. Does acetone treat Vedrigris or only PVC?

TheGoonies1985

Found this:

PVC is a catylist for verdigris formation created by hydrochloric acid forming cupric chloride. PVC damage and verdigris are essentially one in the same.

TheGoonies1985

How do coins develop vedigris? From what?

OAKSTAR

@TheGoonies1985 said:

@OAKSTAR said:
I'm confused between PVC and verdigris. I need pictures.

Vedrigis is that crusty green like sand. PVC is just like toning. That is the way I see it anyways. Maybe I am wrong. Does acetone treat Vedrigris or only PVC?

Then what's this? I don't know how acetone would work on verdigris but it most likely wouldn't make it worse.

For me, VERDI-CARE works great removing PVC or verdigris from old copper coins. I've never tried it on silver.

TheGoonies1985

@OAKSTAR said:

@TheGoonies1985 said:

@OAKSTAR said:
I'm confused between PVC and verdigris. I need pictures.

Vedrigis is that crusty green like sand. PVC is just like toning. That is the way I see it anyways. Maybe I am wrong. Does acetone treat Vedrigris or only PVC?

Then what's this? I don't know how acetone would work on verdigris but it most likely wouldn't make it worse.

For me, VERDI-CARE works great removing PVC or verdigris from old copper coins. I've never tried it on silver.

Says PVC but to me it looks like verdigris small hard green clustered bubbles. I would never buy a coin that any of that (visible anyways).

Say it is PVC I would still never buy such a coin. For me the PVC has to be something I know acetone will fully remove. This I am not sure if it would. Looks to far gone for my liking.

OAKSTAR

And that's why I'm confused..

TheGoonies1985

@OAKSTAR said:
And that's why I'm confused..

Same with me but I draw the line at what I believe is PVC that I know for certain acetone will do its job.

Maybe someone here can help us understand. I would like to know if vedigris is treated with acetone if not they are for sure not the same.

TheGoonies1985

Vedigris almost looks like the coin is ''dying'' from within.

TheGoonies1985

@OAKSTAR said:
And that's why I'm confused..

Found this on the net:

''The deal with acetone is that it's considered good for removing PVC plasticizer residue, which can cause verdigris. It's not any good for removing verdigris in general.

There is a commercial preparation called Verdi-Care which has been formulated to remove verdigris from coins and keep it from coming back, but I've never used it myself.''

OAKSTAR

Yes, that's about my understanding of it as well. Show me a picture of what you consider PVC.

jmlanzaf

@TheGoonies1985 said:

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

What about when working with black electrical tape and the glue on that?

Yes, you can transfer glue or milk or soda or anything else that is on your hands. You are waaay overthinking this or underthinking it.

TheGoonies1985

@OAKSTAR said:
Yes, that's about my understanding of it as well. Show me a picture of what you consider PVC.

This is advanced PVC in my opinion. Never purchased one with this much but was always soft not like bubbles and hard.

This minimal PVC:

This is a lot of PVC:

I guess it changes nothing buy any type of since it is easily treated with acetone. In the end no point worrying since there is a cure and a easy one at that.

TheGoonies1985

@jmlanzaf said:

@TheGoonies1985 said:

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

What about when working with black electrical tape and the glue on that?

Yes, you can transfer glue or milk or soda or anything else that is on your hands. You are waaay overthinking this or underthinking it.

Overthinking like usual. My burden I carry since I was young. I will just let it be since I acetone all my coins anyways. I should just be happy there is a cure for ''coin disease'' aka PVC.

TheGoonies1985

Some say PVC looks milky but I have yet to ever buy a coin that looks milky. I would buy it and acetone it so it would not be an issue.

OAKSTAR

I've always thought of this as verdigris.

TheGoonies1985

@OAKSTAR said:
I've always thought of this as verdigris.

Could be. Looks like PVC to me since it is soft/flat. Someone here may help us sort this out. I enjoy learning so hopefully with come to understand the difference.

TheGoonies1985

This is vedigris:

OAKSTAR

Others with chime in.

OAKSTAR

@TheGoonies1985 said:
This is vedigris:

No, it looks like melted candy.

TheGoonies1985

.

OAKSTAR

You might want to change the title of this thread. PVC or verdigris?

OAKSTAR

....or melted green wax.

OAKSTAR

I should have looked but there are probably dozens of threads on this subject here. The PVC/verdigris thing never really impacted my collecting.

TheGoonies1985

@OAKSTAR said:
I should have looked but there are probably dozens of threads on this subject here. The PVC/verdigris thing never really impacted my collecting.

It would for me depending on how bad it is I would for sure pass on anything that looks like verdigris but that is me.

Mr_Spud

There’s more than one type of verdigris.

4Redisin

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

So, what you are saying is that I can take a Q-tip and rub off all the sticky green stuff on those foreign coin and then put it on a silver dime and copper cent and nothing will happen unless I leave it on them over a period of time - right?

4Redisin

PVC is soft or hazy and verdigris is hard right?

TheGoonies1985

@4Redisin said:
PVC is soft or hazy and verdigris is hard right?

That is what I thought.

jmlanzaf

@OAKSTAR said:

@TheGoonies1985 said:
This is vedigris:

No, it looks like melted candy.

Yes it does.. but it's still verdigris

jmlanzaf

@4Redisin said:

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

So, what you are saying is that I can take a Q-tip and rub off all the sticky green stuff on those foreign coin and then put it on a silver dime and copper cent and nothing will happen unless I leave it on them over a period of time - right?

That's not at all what I said. The sticky green stuff is not fresh and it's NOT PVC. It's residue from the PVC decomposition and plasticizers as I explained above.

You can take a new PVC flip and rub it all over everything and it will create no issues today or 20 years from now.

The sticky residue will not immediately etch the surface, if that's what you are asking. But it won't take 20 years to do so. What takes years is for the PVC itself to break down. The surface damage will happen much more quickly.

Sapyx

"Verdigris", as defined by coin collectors, is crusty dark green deposits that form on coins when exposed to corrosive environments. When analysed, verdigris on copper coins is usually composed of copper carbonate, copper sesquicarbonate and perhaps copper chloride, if the environment was salty as well as corrosive. Verdigris, in this sense, is harmless and not contagious - it won't spontaneously spread from coin to coin and won't deteriorate further upon the coin. The damage has already been done, by whatever it was that caused the corrosion.

There is a particular form of verdigris called "bronze disease", which is of more concern. This is usually in the form of a pale green powdery deposit spontaneously appearing on bronze and copper coins. When analysed, bronze disease is usually a mixture of copper hydroxide and copper sesquicarbonate. It is "contagious" in that it will spontaneously grow, as all it needs to expand is cool moist air. Its powdery form means that little tiny pieces of it can break off the coin and come into contact with other coins, thus allowing the contagion to spread from coin to coin. It can be "killed" by heating in an oven at 105 degrees C, as the sesquicarbonate and hydroxide decompose into copper carbonate and copper oxide.

PVC damage is caused by sulfuric acid, entrapped within the phthalate-plasticized PVC when it is made, slowly leaching out over time; PVC "goo" is made from copper sulfate particles suspended in a slimy mixture of phthalates and perhaps some remnant sulfuric acid. Acetone "works" on PVC goo because it dissolves the phthalates, not because it removes the copper sulfate directly.

Verdigris and bronze disease cannot be treated or removed by acetone; acetone does not react chemically with a coin's surface, so will not remove either metal nor metal compounds. Small or thin deposits of verdigris can be removed via a chelating agent, such as those found in MS70 or similar proprietary mixtures. To treat thick verdigris, you need something corrosive: acids will do the trick, as will concentrated ammonia. The end result will almost certainly be a "cleaned coin", with deep pits left behind where the verdigris used to be.

Verdigris is, essentially, a copper coin problem. By "copper" I include alloys that contain a significant proportion of copper, such as bronze, brass, aluminium-bronze and that 50% silver alloy which those Australian "silver" coins are made from. Coins made of pure or mostly-pure gold or silver should not show verdigris, and indeed rarely show PVC damage. Coins made of pure nickel are likewise mostly unaffected by PVC but may show verdigris-like damage in corrosive environments. And coins made of alloys containing copper (such as coinage silver or coinage gold) only show verdigris under extreme (and usually artificial) environmental conditions.

If a silver coin is turning green (like that Morgan dollar in the above posts), it's almost always because of PVC. The ancient Roman coin posted by Goonies is green because it's (a) not particularly pure silver, and (b) also showing signs of horn silver formation, which is not something that most modern collectors need to worry about as it takes centuries of being buried in salty soil to form.

Mr_Spud

This coin has verdigris on the bottom right reverse about 5 o’clock right on the rim. I didn’t notice it when I purchased it, so it was an accident. I noticed it when I went to take pictures though. So far it hasn’t changed or got worse, I bought it about about 4 years ago. I do make sure it’s protected with intercept shield slab box and whole box in a freezer bag with desiccant. I wonder if it was from sweat on someone’s fingers given that it’s on the rim like that and probably wasn’t evident yet when the coin was slabbed or something like that.

OAKSTAR

@jmlanzaf - Do you really think this is verdigris? The more I look at it, it looks like melted wax.

It almost looks like acetone would remove this stuff.

4Redisin

@4Redisin said:

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

I hate to be a pain on the forum, but it appears that the HARMFUL sticky green stuff forms from the decomposition of the plasticizers and it is the harmful residue that can be transferred to another coin. Then it should be harmful to that coin, right?

4Redisin

@Mr_Spud said:
This coin has verdigris on the bottom right reverse about 5 o’clock right on the rim. I didn’t notice it when I purchased it, so it was an accident. I noticed it when I went to take pictures though. So far it hasn’t changed or got worse, I bought it about about 4 years ago. I do make sure it’s protected with intercept shield slab box and whole box in a freezer bag with desiccant. I wonder if it was from sweat on someone’s fingers given that it’s on the rim like that and probably wasn’t evident yet when the coin was slabbed or something like that.

@Sapyx

Isn't the green on this cent the start of a hard corrosion product like on the ancient?

Barberian

@4Redisin said:

@4Redisin said:

@jmlanzaf said:
You can take a piece of fresh PVC and rub it on every coin you own for hours and NOTHING will happen. PVC is harmless. It's the decomposition ands plasticizers that cause a problem over long periods of time.

If the PVC is tacky, then you can spread the sticky residue which is the decomposition products that are harmful.

I hate to be a pain on the forum, but it appears that the HARMFUL sticky green stuff forms from the decomposition of the plasticizers and it is the harmful residue that can be transferred to another coin. Then it should be harmful to that coin, right?

Yes.

Sapyx

@4Redisin said:
@Sapyx

Isn't the green on this cent the start of a hard corrosion product like on the ancient?

Sort of, yes. The ancient coin is a silver alloy, so is inherently less prone to verdigris /patina formation. However, the encrustation on the ancient would have come from centuries being buried in the earth - it's a mixture of soil and corrosion byproducts from the coin. You probably wouldn't get as much of a raised lump from the modern copper coin if you just left it sitting in the air, exposed to the elements. Copper does expand slightly when it corrodes, but not as much as what we see on that ancient coin.

That ancient coin would almost certainly have been completely covered in that same green encrustation when it was freshly dug up. Someone has partially cleaned it, sufficiently to be able to identify it, then they stopped.

jmlanzaf

@OAKSTAR said:
@jmlanzaf - Do you really think this is verdigris? The more I look at it, it looks like melted wax.

It almost looks like acetone would remove this stuff.

It's "verdigris".

Almost all ancients are dug coins that are cleaned. That's a somewhat clumsy "curating".

OAKSTAR

@TheGoonies1985 said:
This is vedigris:

Is this your coin?

TheGoonies1985

@OAKSTAR said:

@TheGoonies1985 said:
This is vedigris:

Is this your coin?

No. I would never buy a coin that looks like this.

OAKSTAR

@TheGoonies1985 said:

@OAKSTAR said:

@TheGoonies1985 said:
This is vedigris:

Is this your coin?

No. I would never buy a coin that looks like this.

Thank you.