@lkenefic said:
I can state with a fair degree of certainty that this is not due to fungal growth. Fungi typically are saprophytes... they live on dead or decaying organic matter. Unless there was organic matter, and a noticeable amount of it, fungi will not grow. Also, very few fungi produce a blue pigment, and the conditions under which this occurs is typically in a laboratory under controlled conditions.
This looks more like a chemical reaction gone awry... residual chemicals either on the surface of the coin, or on the holder... and then a nice Lewis Acid (such as water) gets into the holder to start the oxidation...
Where did all those chemicals come from? There is conservation of mass, you know.
Looks far more like mold
The chemicals were likely from a previous "dip" and not rinsed properly, or something got spilled and the chemical was introduced into the holder by capillary action and pooled around the coins. As you note, matter cannot be created or destroyed... The mass of the products must equal the mass of the reactants. In this equation, we have the mass of the chemical residue left on the coin, 90% Ag, and since Capital Plastics holders are not air tight, probably water. Note that this can be simply from high humidity. There doesn't need to be a lot of a reactant in order to get dramatic results. I'll let the Physical Chemists in the crowd figure out the chemical equation.
As far as fungus goes... this looks like no fungus I've encountered in the last 35 years of working in and around clinical microbiology... 7 years of it as a microbiologist specifically working the mycology bench. Trust me, it's not a fungus... I'd stake my PhD on it. Of course, we could simply take a sample, suspend it in 40% KOH, and use a light microscope to see if there are hyphael elements indicative of fungi...
I am a Physical Chemist which is why I say that it doesn't look like a chemical reaction. And you have a real mass conservation problem. The silver does not appear pitted and you've had a proliferation of material. There is no foreign chemical substance on the coins capable of doing that.
You also have statistics. An organic material can spread to its neighbors like that. What is the likelihood that 3 coins had the same chemical contaminant and ended up adjacent to each other in the Capitol holder.
In every image of Penicillium that you referenced, there's a large source of organic material for the organism to metabolize... rotting fruit. What, then, is the carbon source? If there were rotting lemons in the Capital Plastics holder, I'd agree...
There is a carbon-based polymer. You have the same but opposite issue with the "chemical reaction" - what is the compound that is growing and spreading independent of anything on the coin? Note that the blue compound has "grown" into the plastic beyond where the coin is located. That is not a chemical reaction on the surface of the coin.
Without a sample, we'll never know for sure.
If the OP wants to scrape some off and send it to me, I have a complete Analytical laboratory at my disposal. Although I'd start with a microscope.
The basic biology of it doesn't make sense for it to be fungal growth. To obtain nutrients, fungi need to grow hyphael elements into the substrate. Think of it as the roots of a tree. In the case of the rotting lemons, the fungi are attached to the lemon via hyphae which metabolize nutrients, which, in turn support the formation of fruiting bodies (spores) which allow the fungus to propagate another generation. Are you suggesting the substrate in this case is the silver coin? The residue left on the coin? Perhaps the OP should have treated these coins with ketoconazole instead...
Collecting: Dansco 7070; Middle Date Large Cents (VF-AU); Box of 20;
Here (https://aem.asm.org/content/85/19/e01095-19) is a good recent review on microbial degradation of plastics. I learned a few things, and I've been a microbiologist for 40 years. Microbes can have difficulty degrading high molecular weight polymers, especially ones not normally found in nature (xenobiotics). We have been eagerly introducing them in huge quantities into the environment for about 80 years, and they have been generally refractory to biodegradation, unlike smaller molecules. That's why they accumulate.
Suffice to say that the blue goo is very unlikely to be microbial growth decomposing the plastics themselves (I couldn't quickly find out which ones are used in Capital holders). If it is, don't throw it out. You just got yourself a Nobel .
The pardon is for tyrants. They like to declare pardons on holidays, such as the birthday of the dictator, or Christ, or the Revolution. Dictators should be encouraged to keep it up. And we should be encouraged to remember that the promiscuous dispensation of clemency is not a sign of political liberality. It is instead one of those valuable, identifying marks of tyranny.
Charles Krauthammer
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
My guess is that liquid was somehow introduced to the holder. No theory I heard here would account for the localized color change. Perhaps some laundry liquid detergent reacted with the plactic? Might account for the blue color. J.P.
These have been to shows? Something could have been spilled while you were distracted.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
Sorry I haven't checked in -- was out of town for the holidays and stayed off the Internet. There was definitely moisture on the affected coins. A local club member who helped man my table at either the 2016 or 2017 Texas Numismatic Association show in Arlington, Texas remembers seeing that set, and also that on the last day of the show, when dealers were leaving, waves of heavy rain that lasted about a minute drenched us and many other dealers, seemed to be over only to start again when the next dealer got halfway to his car. I remember (well, with some help from my younger helper) that the storage containers we used with interlocking lids (photo) had let quite a bit of water in during threk,. I had to discard all the cardboard slab boxes which were damp while setting fans out and making sure everything was dry. I remember looking at the Walker set and it seemed dry, but knowing that capillary action can suck water in from the edges, I should have taken it apart and made sure it was completely dry. So some contamination on the coins, probably dip residue, PVC or both, combined with small amount of moisture and a few years can really destroy a coin. I looked at them with a stereo microscope and the coins are fatally damaged with the metal destroyed.
Also, I remember that I bought this the same time I bought a 25th anniversary wedding year Capital holder for my parents, which I filled with coins from a 1956 proof set. So that dates the holder to 1981. And there were a couple of Walkers that rotated and rattled, and was told putting a layer of fingernail polish on the loose opening -- or cut a piece from a flip to use as a shim --- wondering if i might have done #2 and used a PVC flip --- wasn't that before the warning about PVC came out?
I guess the only thing that can be said for certain is inspect coins every year or two, and there are always good-intention time bombs waiting to explode...
Frank Provasek - PCGS Authorized Dealer, Life Member ANA, Member TNA. www.frankcoins.com
So, a plausible scenario would be, some substance ( dip residue the most likely ) was on the 3 coins, perhaps mostly in the reeds of the edge and in the recesses of the devices. This could be from a full-strength dip followed by a quick rinse and a pat dry, and could have been by a previous owner, or whoever put the set together.
The coins looked fine, and likely would have kept looking great, until the set got damp during the rain incident described, toweled off but not disassembled and aired out.
The moisture wicked into the set by capillary action, dissolved and spread the residue, then slowly dried again, causing the corrosion color, residue, and damage observed.
@Baley said:
So, a plausible scenario would be, some substance ( dip residue the most likely ) was on the 3 coins, perhaps mostly in the reeds of the edge and in the recesses of the devices. This could be from a full-strength dip followed by a quick rinse and a pat dry, and could have been by a previous owner, or whoever put the set together.
The coins looked fine, and likely would have kept looking great, until the set got damp during the rain incident described, toweled off but not disassembled and aired out.
The moisture wicked into the set by capillary action, dissolved and spread the residue, then slowly dried again, causing the corrosion color, residue, and damage observed.
But there really seems to be a conservation of mass issue which I think is part of what Insider is referring to. So a thin film of residue mixed with a little water doesn't create a thick film of anything. It really looks like more than water had to be added to the system.
All comments reflect the opinion of the author, evn when irrefutably accurate.
I don't think there is all that much mass between the plastic, that's a very small volume. The pictures in the holder as found clearly show evidence of liquid pooling and drying. I think the matter we see are compounds of silver corroded off of the coins, the dip, the water, and the air. It all adds up. Ever see that "fluffy powder" that sometimes accumulates on car battery terminals? Where does that mass "come from"?
We'd need more information, an alternative hypothesis, or both, to understand additional substances.
Edit, or, some of you do.😉
The OP and I seem to be on the same page, along with several others.
@3stars said:
The difference between a genius and a know it all is...
I'll take a wild guess...The genius has been on the forums for at least TEN YEARS, has started less than 100 discussions, and left less than 1K comments. The genius rating is well deserved as it proves the genius actually has a LIFE AWAY FROM CU."
I don't think there is all that much mass between the plastic, that's a very small volume. The pictures in the holder as found clearly show evidence of liquid pooling and drying. I think the matter we see are compounds of silver corroded off of the coins, the dip, the water, and the air. It all adds up. Ever see that "fluffy powder" that sometimes accumulates on car battery terminals? Where does that mass "come from"?
We'd need more information, an alternative hypothesis, or both, to understand additional substances.
Edit, or, some of you do.😉
The OP and I seem to be on the same page, along with several others.
The fluffy powder is usually due to acid on metal, not just water.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@3stars said:
The difference between a genius and a know it all is...
I'll take a wild guess...The genius has been on the forums for at least TEN YEARS, has started less than 100 discussions, and left less than 1K comments. The genius rating is well deserved as it proves the genius actually has a LIFE AWAY FROM CU."
The ONLY know-it-all I know is my lovely wife.
Does your business card read, "Five Star Contributor to the PCGS Forums"? It should if it doesn't.
@3stars said:
The difference between a genius and a know it all is...
I'll take a wild guess...The genius has been on the forums for at least TEN YEARS, has started less than 100 discussions, and left less than 1K comments. The genius rating is well deserved as it proves the genius actually has a LIFE AWAY FROM CU."
The ONLY know-it-all I know is my lovely wife.
Does your business card read, "Five Star Contributor to the PCGS Forums"? It should if it doesn't.
His business card simply says "I'll call you."
He is.................... The Most Interesting Man In The World.
That would be Jonathan Goldsmith. Watch for him on a bunch of Gunsmoke episodes.
The pardon is for tyrants. They like to declare pardons on holidays, such as the birthday of the dictator, or Christ, or the Revolution. Dictators should be encouraged to keep it up. And we should be encouraged to remember that the promiscuous dispensation of clemency is not a sign of political liberality. It is instead one of those valuable, identifying marks of tyranny.
Charles Krauthammer
Comments
The etching would be due to some byproduct, not the mold actually eating it.
https://sciencemag.org/news/2016/03/iron-eating-fungus-disintegrates-rocks-acid-and-cellular-knives
All comments reflect the opinion of the author, evn when irrefutably accurate.
https://mediamatic.net/en/page/16715/mold-that-eats-plastic
All comments reflect the opinion of the author, evn when irrefutably accurate.
The basic biology of it doesn't make sense for it to be fungal growth. To obtain nutrients, fungi need to grow hyphael elements into the substrate. Think of it as the roots of a tree. In the case of the rotting lemons, the fungi are attached to the lemon via hyphae which metabolize nutrients, which, in turn support the formation of fruiting bodies (spores) which allow the fungus to propagate another generation. Are you suggesting the substrate in this case is the silver coin? The residue left on the coin? Perhaps the OP should have treated these coins with ketoconazole instead...
Successful BST transactions with: SilverEagles92; Ahrensdad; Smitty; GregHansen; Lablade; Mercury10c; copperflopper; whatsup; KISHU1; scrapman1077, crispy, canadanz, smallchange, robkool, Mission16, ranshdow, ibzman350, Fallguy, Collectorcoins, SurfinxHI, jwitten, Walkerguy21D, dsessom.
No Way Out: Stimulus and Money Printing Are the Only Path Left
Here (https://aem.asm.org/content/85/19/e01095-19) is a good recent review on microbial degradation of plastics. I learned a few things, and I've been a microbiologist for 40 years. Microbes can have difficulty degrading high molecular weight polymers, especially ones not normally found in nature (xenobiotics). We have been eagerly introducing them in huge quantities into the environment for about 80 years, and they have been generally refractory to biodegradation, unlike smaller molecules. That's why they accumulate.
Suffice to say that the blue goo is very unlikely to be microbial growth decomposing the plastics themselves (I couldn't quickly find out which ones are used in Capital holders). If it is, don't throw it out. You just got yourself a Nobel
.
The pardon is for tyrants. They like to declare pardons on holidays, such as the birthday of the dictator, or Christ, or the Revolution. Dictators should be encouraged to keep it up. And we should be encouraged to remember that the promiscuous dispensation of clemency is not a sign of political liberality. It is instead one of those valuable, identifying marks of tyranny.
Charles Krauthammer
Blue Man Goop?
PMD vs error. Chemical reaction vs biological. The forum is sure in a debatatory mood lately.
There’s a lot of copper in those coins. Copper compounds are commonly blue. I vote non-biologic, but that’s just a guess.
My guess is that liquid was somehow introduced to the holder. No theory I heard here would account for the localized color change. Perhaps some laundry liquid detergent reacted with the plactic? Might account for the blue color. J.P.
Here is part of a set I’ve had for 14 years now, no problem so far. They aren’t even beginning to tone
These have been to shows? Something could have been spilled while you were distracted.
LOL!
Wouldn't mustard stains be yellow?
See http://www.doubledimes.com for a free online reference for US twenty-cent pieces
OMG !!!
Sorry I haven't checked in -- was out of town for the holidays and stayed off the Internet. There was definitely moisture on the affected coins. A local club member who helped man my table at either the 2016 or 2017 Texas Numismatic Association show in Arlington, Texas remembers seeing that set, and also that on the last day of the show, when dealers were leaving, waves of heavy rain that lasted about a minute drenched us and many other dealers, seemed to be over only to start again when the next dealer got halfway to his car. I remember (well, with some help from my younger helper) that the storage containers we used with interlocking lids (photo) had let quite a bit of water in during threk,. I had to discard all the cardboard slab boxes which were damp while setting fans out and making sure everything was dry. I remember looking at the Walker set and it seemed dry, but knowing that capillary action can suck water in from the edges, I should have taken it apart and made sure it was completely dry. So some contamination on the coins, probably dip residue, PVC or both, combined with small amount of moisture and a few years can really destroy a coin. I looked at them with a stereo microscope and the coins are fatally damaged with the metal destroyed.
Also, I remember that I bought this the same time I bought a 25th anniversary wedding year Capital holder for my parents, which I filled with coins from a 1956 proof set. So that dates the holder to 1981. And there were a couple of Walkers that rotated and rattled, and was told putting a layer of fingernail polish on the loose opening -- or cut a piece from a flip to use as a shim --- wondering if i might have done #2 and used a PVC flip --- wasn't that before the warning about PVC came out?
I guess the only thing that can be said for certain is inspect coins every year or two, and there are always good-intention time bombs waiting to explode...
Coins dipped, not rinsed completely IMHO
Sorry to see that.
100% Positive BST transactions
Old dip residue usually turns BROWN. It should not affect the plastic at all.
It's good to see Frank posting. I'm sorry for the subject matter. Ouch. That hurts.
"Inspiration exists, but it has to find you working" Pablo Picasso
A lot of things can be "dipped", put on or wiped on a coin surface and/or edge is what I meant.
100% Positive BST transactions
Yes but it should not FLOW on to the plastic unless the coins were ""run hard and put away wet" causing them to become corroded.
Did you read Frankcoin's follow up post?
Or just not understand?
That's exactly what happened.
Liberty: Parent of Science & Industry
I think you misunderstand @Insider2
I would also add: corrosion doesn't run away from the surface.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@Baley asked: "Did you read Frankcoin's follow up post?"
NO. I wonder why only a few coins were affected.
So, a plausible scenario would be, some substance ( dip residue the most likely ) was on the 3 coins, perhaps mostly in the reeds of the edge and in the recesses of the devices. This could be from a full-strength dip followed by a quick rinse and a pat dry, and could have been by a previous owner, or whoever put the set together.
The coins looked fine, and likely would have kept looking great, until the set got damp during the rain incident described, toweled off but not disassembled and aired out.
The moisture wicked into the set by capillary action, dissolved and spread the residue, then slowly dried again, causing the corrosion color, residue, and damage observed.
Liberty: Parent of Science & Industry
The difference between a genius and a know it all is...
Gotta be the same thing that stole Superman's power. Kryptonite.
``https://ebay.us/m/KxolR5
But there really seems to be a conservation of mass issue which I think is part of what Insider is referring to. So a thin film of residue mixed with a little water doesn't create a thick film of anything. It really looks like more than water had to be added to the system.
All comments reflect the opinion of the author, evn when irrefutably accurate.
Great conversation!
Such as... ?
I don't think there is all that much mass between the plastic, that's a very small volume. The pictures in the holder as found clearly show evidence of liquid pooling and drying. I think the matter we see are compounds of silver corroded off of the coins, the dip, the water, and the air. It all adds up. Ever see that "fluffy powder" that sometimes accumulates on car battery terminals? Where does that mass "come from"?
We'd need more information, an alternative hypothesis, or both, to understand additional substances.
Edit, or, some of you do.😉
The OP and I seem to be on the same page, along with several others.
Liberty: Parent of Science & Industry
I'll take a wild guess...The genius has been on the forums for at least TEN YEARS, has started less than 100 discussions, and left less than 1K comments. The genius rating is well deserved as it proves the genius actually has a LIFE AWAY FROM CU."
The ONLY know-it-all I know is my lovely wife.
The fluffy powder is usually due to acid on metal, not just water.
All comments reflect the opinion of the author, evn when irrefutably accurate.
Does your business card read, "Five Star Contributor to the PCGS Forums"? It should if it doesn't.
peacockcoins
His business card simply says "I'll call you."
He is.................... The Most Interesting Man In The World.
That would be Jonathan Goldsmith. Watch for him on a bunch of Gunsmoke episodes.
The pardon is for tyrants. They like to declare pardons on holidays, such as the birthday of the dictator, or Christ, or the Revolution. Dictators should be encouraged to keep it up. And we should be encouraged to remember that the promiscuous dispensation of clemency is not a sign of political liberality. It is instead one of those valuable, identifying marks of tyranny.
Charles Krauthammer
Silver is anti-microbial, so it isn't organic.