Verdigone

I've heard many times that verdigris will infect other coins that it comes in contact with, or that if it is only partially removed with Verdigone or some mechanical means then it will return. Can anyone point to a reference or pictures that confirm either of these two scenarios? Or is this just an unproven urban myth?

 

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and how do u propose we provide pics of verdi returning? it has been scientifically proven that verdi returns because it is nothing but a self feeding chemical reaction i believe one of the members had put up the exact reaction.

however my own theory is an unproven urban myth except i see it happen all the time

 

We think the same way. I have wondered that as well. Here are the results of a few months of vd and non vd stored together in an open container.

 

I'm scared to even have the pic in with my other coin pics. If the pics change too, I'll let you know.

 

Where is the reference for the "scientific proof"?

The statement that it returns or is transferrable is stated as truth but with no verification that I can find. There is no such thing as a "self feeding chemical reaction". A reaction occurs when two or more reactive chemicals come in contact with other. Continuing reactions can only occur with the addition of more of the same chemicals. If chlorine comes in contact with copper and forms verdigris, no further verdigris can be formed unless more chlorine is introduced, regardless of the amount of verdigris that has already formed.

Any chemists here that care to weigh in on this?

 

I can't see if your pictures are an argument for or against what I said. Without knowing which coins were infected before and which ones may or may not have been infected after there is no way to determine the effects of contact or even if the amount present has increased.

 

Roll searching, I go through and take out the worst coins. Then I go through and sort by decade and then by date. I take out all the ones with VD as I find them. These are from the decade and year specific sort, so there was less VD on these (in general) than the first sort. More than a few did not have any issues when I put them in, but were not DD,RPM etc. (I don't have exact percentages). Now, most all have issues. The coppers have less issues than the zincolns. It was not scientific, just wanted to see what would happen. I will leave this as it is and take more pics in a few months for you to compare. Climate=Michigan, your results may vary.

 

you dont need a chemist. moisture is the ingredient if you google it or search CT u will get that information

 

I have googled it and found nothing to answer the question I asked (maybe you could point me to the correct reference?). Searching CT provides opinion but no proof.

And moisture (water - H2O) is not "the ingredient". Water is neutral and non-reactive with most elements. It reacts only with electropositive elements such as lithium, sodium, calcium, potassium and caesium.

 

i am surprised ill go look for it there used to be a whole power point slide

i will let you figure the moisture thing out yourself since you are already convinced

 

here this is what comes up on google

http://72.14.235.132/search?q=cache...ion&hl=en&ct=clnk&cd=1&gl=in&client=firefox-a

and here is another

http://en.wikipedia.org/wiki/Verdigris

although i must say i no longer have the power point slide that explained it well perhaps lost it when i installed win 7

 

Did you even read the two references you provided?

The first is a high school project to see if different organic substances would produce verdigris. They used Asparagus, Milk of Magnesia, Lemon, Water, Kiwi, Coca-cola, Milk, Butter, Bread, Sugar, Vitamin and Captain Crunch with milk. They did produce some verdigris but nothing in their findings indicated that verdigris is infectious or would expand without continued exposure to the materials that produced it in the first place.

The second reference - Wikipedia - describes the chemistry of, and chemical makeup of verdigris, but again, nothing presented indicates that verdigris is infectious or would expand without continued exposure to the materials that produced it in the first place.

BadThad - Are you out there?

 

did u read the link provided in wiki? verdi is actually a fungicide so its not infectious but does it spread absolutely and bad thad will tell you the same thing or desert gem or GD

 

Yes Spock, I did read the article and the links provided, and nothing in the article or the links says anything about verdigris being infectious to previously uninfected areas of copper, nor that it is self-replicating in the absence of carbonates, chlorides or acetates.

The fact that verdigris is a fungicide ("Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores") has absolutely nothing to do with the formation of verdigris in the first place. Your statement, "verdi is a fungicide...but it does spread..." is a total non-sequitur. It makes no sense in itself and provides no insight to the discussion at hand.

Verdigris is formed when the coin is exposed to some carbonate, chloride or acetate contaminate. I contend that once the coin is removed from source of the contamination then the further production of verdigris stops (the verdigris present does not spawn more verdigris). Finally I contend that unaffected copper which comes in contact with verdigris on another coin will not become contaminated by that verdigris as long as the contaminate that caused the verdigris is no longer present.

My original question remains unanswered.

 

Verdigris is composed of copper compounds of acetate, carbonate, sulfate and chloride. Pure water or moisture in of itself does not cause verdigris, however, impurities present in water (namely carbon dioxide) can cause verdigris and it also acts of a sort of catalyst for the reaction, mainly as a transport mechanism.

Verdigris can absolutely spread, especially in the presence of moisture. The humidity in air is sufficent. If the above mentioned compounds are present, they can migrate to any surface the rate of which would be primarily defined by the amount of water around the coins, which can act as a transport mechanism. Bottomline, keep coins with verdigris separate and protect them from air and moisture.

That said....verdigris is NOT a living organism, it's simply the result of a chemical reaction. Matter cannot be created from nothing and it cannot "grow" without being fed. A coin that has the verdigris removed and then protected from air/moisture in a device like an Airtite holder will NOT "regrow" verdigris. It's not possible since there's no "feed" materials to produce the reaction.

 

I believe you are saying what I have been saying - if verdigris has developed on a coin and the coin is removed from the influences of the acetates, carbonates, sulfates or chlorides that produced it, then it will not continue to grow, e.g., if a coin in Montanna develops verdigris after having been mishandled and/or stored in a PVC holder is removed from the holder and sold to someone in Arizona, then the growth of the verdigris will stop when it is in its new home without the contaminates which caused the verdigris.

One point of clarification would be appreciated - if there is verdigris on a coin, is that verdigris stable in the sense that it is the end result of the reaction(s) that caused it? Or are there still free acetates, carbonates, sulfates or chlorides present just waiting for moisture to continue the process anew? IF that is the case then I can see how physical contact with a fresh coin could start the process on the second coin or could continue on the original coin.

 

Yes, the reaction is essentially finished unless there's free anionic materials still present. Of course the process can continue if there's free anionic material present, it's not "satisfied" until it combines with a cationic material like copper. In the presence of water, verdigris can partially dissociate creating fresh anions looking for a happy place to attach, i.e. another coin.

My recommendation...if you don't want to attempt removal of the verdigris: rinse the coin with distilled water, acetone and then xylene and then put it in an Airtite. The rinsing procedure should remove any possible reactants and halt the process. The verdigris cannot continue to form after doing this.