<< <i>I don't do much with ASE's, but have heard that NGC coins don't spot as often. Check out what differences there are between your slab composition and theirs, and see what the difference is.
I've seen a number of green label PCI slabbed ASE's with absolutely no spots, maybe you should model your plastic after theirs.
idk, food for thought >>
So is there a point in time during which the problem seems to have gotten noticeably worse like in say the last couple of years? Or has it always been something of a low level problem that just never got much air time? seems like you hear more about with recent ASE dated issues than 1986 or 1987 issue coins.
Wouldn't surprise me that the planchets are actually coming from China or India.
I had a pretty good set of PCGS MS69 Eagles and ended up selling them for nothing. Almost all of them had spotted up and spotted badly. Very ugly coins! I lost alot of $$$ there.
since this is the only thread or article about milk spotting that has any PCGS officials posting, other than the January 7, 2008 Coin World article, I will post my theory on cause, treatment and prevention here.
milk spots cause -
a chemical reaction with AG+ (on the coin) and Cl- (in the air) to form AgCl on the surface of the coin, similar to toning or PVC contamination it is more prevalent on 99.9% silver coins (ASEs), but also can be found on 90% silver but more noticable or distracting on proof coins with deep mirrors
originally found on the surface but after continued exposure, can etch into the coin like PVC contamination can be found prestrike, or post strike and can start at any time with the exposure of free Cl- exposure usually by Cl- in the air and more prevalent near salt water
treatment -
dip in ammonia solution and then neutralize/dilute with dip in distilled water and final dip in acetone if metal already etched, may leave small pits if struck into the coin, dips may not get to contaminant
prevention -
after treatment, keep in airtight container - either wrap in something (like aluminum foil) or have dessicant in container like glass jar - at this time, slabs are NOT airtight, so additional protection is needed
good luck and practice on some lower valued coins and remember, if you drink too much of anything (including water), you may die
<< <i>As far as I know NGC and ANACS dont have the milk spotting problem, or at least not to the extent that PCGS does. I'm not the sharpest knife in the drawer but isnt Newport Beach, CA geographically located between the Pacific Ocean and Newport Bay. The salt in the air is so thick you can smell it. When employees come in from outside it's on their clothes and in their hair so any special filtration systems or clean rooms are instantly contaminated. >>
Good point, we had a customer in India who had such an inordinate amount of hardware failures we contracted to have the parts analyzed. Turns out there was so much sulfur dioxide in the air it was corroding the circuit boards. Solution, put in a big air filter. SAE's are 5 nine silver, it would not take much of a contaminate to spot them.
It's the wash. They can be dipped and rinsed in distilled water, and they would be fine; however, that would make you a coin doctor and the sniffer would catch the dip, so the answer is there is no answer without dipping.
President, Racine Numismatic Society 2013-2014; Variety Resource Dimes; See 6/8/12 CDN for my article on Winged Liberty Dimes; Ebay
<< <i>It's the wash. They can be dipped and rinsed in distilled water, and they would be fine; however, that would make you a coin doctor and the sniffer would catch the dip, so the answer is there is no answer without dipping. >>
I would try boiling a new unspotted coin in distilled water instead of just rinsing.
<< <i>since this is the only thread or article about milk spotting that has any PCGS officials posting, other than the January 7, 2008 Coin World article, I will post my theory on cause, treatment and prevention here.
milk spots cause -
a chemical reaction with AG+ (on the coin) and Cl- (in the air) to form AgCl on the surface of the coin, similar to toning or PVC contamination it is more prevalent on 99.9% silver coins (ASEs), but also can be found on 90% silver but more noticable or distracting on proof coins with deep mirrors
originally found on the surface but after continued exposure, can etch into the coin like PVC contamination can be found prestrike, or post strike and can start at any time with the exposure of free Cl- exposure usually by Cl- in the air and more prevalent near salt water
treatment -
dip in ammonia solution and then neutralize/dilute with dip in distilled water and final dip in acetone if metal already etched, may leave small pits if struck into the coin, dips may not get to contaminant
prevention -
after treatment, keep in airtight container - either wrap in something (like aluminum foil) or have dessicant in container like glass jar - at this time, slabs are NOT airtight, so additional protection is needed
good luck and practice on some lower valued coins and remember, if you drink too much of anything (including water), you may die >>
I think you have a bit more splainin to do.
It is found on coins in NGC slabs and on coins from new mint tubes too. If it was air borne chloride shouldn't it affect all coins and not just ASEs and shouldn't it affect all ASEs?
How do you explain the appearance as round spots or sometimes irregular shaped spots? If twas airborne the entire coin should be affected. Seems to me it is deposits left after evaporation of a liquid.
<< <i>SAE's are 5 nine silver, it would not take much of a contaminate to spot them. >>
SAE's are 3 nine silver. Canadian Maples are 4 nine silver and I see more spotting on them right out of the monster box. >>
you are correct, my bad. they are .999 fine, I was thinking 99.999 fine, which is 5 ninse but they are 99.9% silver.
BTW -I will add, that I don't own a single SAE that has milk spotted, I have had a couple of hundred, PCGS, mint packaging, proof, non proof. Some I have had since 86.
It's a trick !! The one's with spots could be worth more . If that happens then we would never see them again . Or add them to my 401K . The spots would be gone. Ron
Viet Nam Vet 66/67. Retired Coin Shop Owner . Still Collecting Love my Grandkids and my German Shepherd Dogs . Kind of like my wifes Cat.
Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC?
<< <i>Why people slab bullion I will never understand. >>
Well not all of it is created equal and some do more than just stack it in the corner. Plus it provides a revenue stream for our hosts to have enough money to host this forum. BTW aboard.
My original theory was that if a TPG ever used compressed air to give the coins a blast to clean the coins before encapsulating them, there may condensation in the line and small particles of water, unseen to the eye, would land on the coin and the end result would be the appearance of milk spots.
I do not know if the TPG's give the coins a blast of air or not before slabbing, it was just the only thing I could think of since I have had it happen when painting cars using an air compressor. If the condensation is not out of the line, it will invariably wind up on the car and is noticeable in the final product.
I have seen videos of the US mint using compressed air to clean the coins one last time before encapsulating. This may be the reason that some of the coins develop spots while still in the OGP, if condensation is in the air line used to clean the coins.
The video was on one of the cable channels on a program about the US Mint. I don't recall the name of the episode though.
Air lines are notorious for propelling moisture and even oil in a vaporized form. Saw it many times in industry. Not at all sure this is the cause of milk spots, but worth considering. Cheers, RickO
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots?
It is possible to produce dry compressed air if the need is there. For many industrial uses it is either unnecessary or they figure it is cheaper to cover the expense of maintenance rather than maintain an expensive process.
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots? >>
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots? >>
same coin no spots for me, sometimes they forget to remove a "dip" tag from the slab (whatever for?) not that the slab gets dipped..lol
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots? >>
same coin no spots for me, sometimes they forget to remove a "dip" tag from the slab (whatever for?) not that the slab gets dipped..lol >>
Makes me wonder if the spot is the same as the other milk spots we have heard about or if they finally have a solution for it (pun intended )? From what I recall during the ASE heydays of collecting, once the milk spot showed up, it was too late and couldn't be gotten rid of.
Cause and solution were provided long ago, but never acknowledged. Production and examination conditions might have changed, so the subject would require complete reexamination.
@Russ said:
A quick dip to stabilize the surfaces BEFORE submitting solves the problem. I'd like my $50K in small bills, please.
Russ, NCNE
Who in the HELL is gonna dip 25,000 ASEs?
You realize you're talking to a dead man.
Indeed I do. Was just intended as a comment to the crowd and not a response to the poster. Without rereading the the whole thread [I know it's OLD] there are a lot of old names [Dorkkarl was banned? I did not know that] and a lot of bullchit and speculation.
One thing that PCGS could have done[and maybe did] was simply reholdered a new ASE and sold off the spotted ones instead of spending countless hours trying to conserve them.
One thing I've posted that ALWAYS seems to fall on deaf ears is that it's been said that one can see the spots BEFORE they become visible by looking at it using a halogen flashlight. At this point they can be removed by dipping in EZest. Once visible they are there for good. The spots are silver chloride and silver chloride is NOT soluble in acetone. There may be more than one cause of the spots. Some look white and some are tea colored. Chloride presence suggests that there was a hydrochloric acid wash somewhere in the process that was never properly washed/rinsed off. IIRC the mint started using the HCl wash back in 1921 which probably explains 1921 Morgans and Peace dollars tone differently from earlier Morgans.
Also here is a scanning electron micrograph of the surface of an ASE.
The spots tend to form at the roughest areas of the coin surface.
@BAJJERFAN said: "The spots tend to form at the roughest areas of the coin surface."
Please clarify. At those powers, the entire surface is rough. Therefore, in order to convince me of the "truth" of your opinion ("The spots tend to form at the roughest areas of the coin surface.") I'd need to see a spot and the area around it. In fact, more than in one place because as the person taking the image to prove your point, it would be possible to choose what area to image - a spot in a really rough area.
What does make sense is that the roughness would be more likely to "trap" chemicals.
IMO many spots on holdered coins are caused by faulty filtering of the air used to blow out the coin and cases. You can actually see the "vapor" come out of the nozzle.
@Insider2 said: @BAJJERFAN said: "The spots tend to form at the roughest areas of the coin surface."
Please clarify. At those powers, the entire surface is rough. Therefore, in order to convince me of the "truth" of your opinion ("The spots tend to form at the roughest areas of the coin surface.") I'd need to see a spot and the area around it. In fact, more than in one place because as the person taking the image to prove your point, it would be possible to choose what area to image - a spot in a really rough area.
What does make sense is that the roughness would be more likely to "trap" chemicals.
IMO many spots on holdered coins are caused by faulty filtering of the air used to blow out the coin and cases. You can actually see the "vapor" come out of the nozzle.
That's not my opinion. It was the opinion/observation of the tech who assisted me in checking out the spots on a silver eagle.
First order of business was to examine the spot using a technique called XPS X-ray Photoelectron Spectroscopy [aka ESCA Electron Spectroscopy Chemical Analysis] with the help of a scientist at the Ames Laboratory. He found only other element besides silver was chlorine.
He also looked at the coin surface with a high magnification microscope and did or had someone do the SEM work. His observation was that droplets remaining on a coin surface tended to accumulate at the rougher areas; a not unexpected conclusion.
You can't filter water out of compressed air. You either need a dryer system to remove it or a chiller of some type to freeze or condense it out. Moisture in compressed air should be essentially like distilled water so if it gets on a coin surface it shouldn't deposit anything. Sometimes if one spills water on something it leaves a lighter looking spot. I'm pretty sure it is not the reason for the spots on ASEs, esp. since they can be spotted right from the mint tube.
@Insider2 said: @BAJJERFAN said: "The spots tend to form at the roughest areas of the coin surface."
Please clarify. At those powers, the entire surface is rough. Therefore, in order to convince me of the "truth" of your opinion ("The spots tend to form at the roughest areas of the coin surface.") I'd need to see a spot and the area around it. In fact, more than in one place because as the person taking the image to prove your point, it would be possible to choose what area to image - a spot in a really rough area.
What does make sense is that the roughness would be more likely to "trap" chemicals.
IMO many spots on holdered coins are caused by faulty filtering of the air used to blow out the coin and cases. You can actually see the "vapor" come out of the nozzle.
That's not my opinion. It was the opinion/observation of the tech who assisted me in checking out the spots on a silver eagle.
First order of business was to examine the spot using a technique called XPS X-ray Photoelectron Spectroscopy [aka ESCA Electron Spectroscopy Chemical Analysis] with the help of a scientist at the Ames Laboratory. He found only other element besides silver was chlorine.
He also looked at the coin surface with a high magnification microscope and did or had someone do the SEM work. His observation was that droplets remaining on a coin surface tended to accumulate at the rougher areas; a not unexpected conclusion.
You can't filter water out of compressed air. You either need a dryer system to remove it or a chiller of some type to freeze or condense it out. Moisture in compressed air should be essentially like distilled water so if it gets on a coin surface it shouldn't deposit anything. Sometimes if one spills water on something it leaves a lighter looking spot. I'm pretty sure it is not the reason for the spots on ASEs, esp. since they can be spotted right from the mint tube.
As I posted, it makes sense that the spots would occur where something would be more likely to accumulate and trap them.
AFAIK, no TPGS uses "a dryer system to remove it or a chiller of some type to freeze or condense it [water vapor] out." As for this: "Moisture in compressed air should be essentially like distilled water. ** All well and fine except the air goes through hoses and nozzles that can contaminate the air. While everyone knows SE coins come spotted from the mint,I assure you from personal experience (actual TESTS) inside a TPGS** that "virgin" coins will spot with the air hoses!
Finely, the coins from the mint do not have droplets on them. His experiment proves what should be obvious. However, the scientist may wish to do the experiment I recommended on DRY coins with spots.
@BAJJERFAN said:
One thing I've posted that ALWAYS seems to fall on deaf ears is that it's been said that one can see the spots BEFORE they become visible by looking at it using a halogen flashlight. At this point they can be removed by dipping in EZest. Once visible they are there for good. The spots are silver chloride and silver chloride is NOT soluble in acetone. There may be more than one cause of the spots. Some look white and some are tea colored. Chloride presence suggests that there was a hydrochloric acid wash somewhere in the process that was never properly washed/rinsed off. IIRC the mint started using the HCl wash back in 1921 which probably explains 1921 Morgans and Peace dollars tone differently from earlier Morgans.
Also here is a scanning electron micrograph of the surface of an ASE.
The spots tend to form at the roughest areas of the coin surface.
 then it has to be another metal salt. It can't be "invisible" silver chloride because why would the silver chloride grow without the introduction of more chlorine.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@Insider2 said: @BAJJERFAN said: "The spots tend to form at the roughest areas of the coin surface."
Please clarify. At those powers, the entire surface is rough. Therefore, in order to convince me of the "truth" of your opinion ("The spots tend to form at the roughest areas of the coin surface.") I'd need to see a spot and the area around it. In fact, more than in one place because as the person taking the image to prove your point, it would be possible to choose what area to image - a spot in a really rough area.
What does make sense is that the roughness would be more likely to "trap" chemicals.
IMO many spots on holdered coins are caused by faulty filtering of the air used to blow out the coin and cases. You can actually see the "vapor" come out of the nozzle.
That's not my opinion. It was the opinion/observation of the tech who assisted me in checking out the spots on a silver eagle.
First order of business was to examine the spot using a technique called XPS X-ray Photoelectron Spectroscopy [aka ESCA Electron Spectroscopy Chemical Analysis] with the help of a scientist at the Ames Laboratory. He found only other element besides silver was chlorine.
He also looked at the coin surface with a high magnification microscope and did or had someone do the SEM work. His observation was that droplets remaining on a coin surface tended to accumulate at the rougher areas; a not unexpected conclusion.
You can't filter water out of compressed air. You either need a dryer system to remove it or a chiller of some type to freeze or condense it out. Moisture in compressed air should be essentially like distilled water so if it gets on a coin surface it shouldn't deposit anything. Sometimes if one spills water on something it leaves a lighter looking spot. I'm pretty sure it is not the reason for the spots on ASEs, esp. since they can be spotted right from the mint tube.
As I posted, it makes sense that the spots would occur where something would be more likely to accumulate and trap them.
AFAIK, no TPGS uses "a dryer system to remove it or a chiller of some type to freeze or condense it [water vapor] out." As for this: "Moisture in compressed air should be essentially like distilled water. ** All well and fine except the air goes through hoses and nozzles that can contaminate the air. While everyone knows SE coins come spotted from the mint,I assure you from personal experience (actual TESTS) inside a TPGS** that "virgin" coins will spot with the air hoses!
Finely, the coins from the mint do not have droplets on them. His experiment proves what should be obvious. However, the scientist may wish to do the experiment I recommended on DRY coins with spots.
The scientist isn't there anymore. What he did was done gratis since they normally would charge for it.
Also the TPGs use the same compressed air for all coins, no? Why don't they have complaints about water-spotting on other coins? Or do they? Unless it's some sort of mold the contamination in hoses and nozzles left long ago. If water in the compressed air was an issue they would or should have addressed it long ago, unless it is so magical that it affects only silver bullion and nothing else.
Of course coins from the mint don't have spots on them, but the roundish nature of the dry spots suggests that they were droplets at some point.
@BAJJERFAN said:
One thing I've posted that ALWAYS seems to fall on deaf ears is that it's been said that one can see the spots BEFORE they become visible by looking at it using a halogen flashlight. At this point they can be removed by dipping in EZest. Once visible they are there for good. The spots are silver chloride and silver chloride is NOT soluble in acetone. There may be more than one cause of the spots. Some look white and some are tea colored. Chloride presence suggests that there was a hydrochloric acid wash somewhere in the process that was never properly washed/rinsed off. IIRC the mint started using the HCl wash back in 1921 which probably explains 1921 Morgans and Peace dollars tone differently from earlier Morgans.
Also here is a scanning electron micrograph of the surface of an ASE.
The spots tend to form at the roughest areas of the coin surface.
 then it has to be another metal salt. It can't be "invisible" silver chloride because why would the silver chloride grow without the introduction of more chlorine.
Why can't it be silver chloride bound to the surface? Also it is known that silver chloride does weird things and becomes less soluble once exposed to light. I had a good reference for that, but it somehow got changed or corrupted. IMO there is some sort of species left on the planchet/coin that undergoes a latent slow change when exposed to air and/or UV light. This whole deal would be great thesis topic for a student in physical or surface chemistry.
All we found is chloride. No sodium, calcium, magnesium or any common mineral found in water.
hloride grow without the introduction of more chlorine.
Why can't it be silver chloride bound to the surface? Also it is known that silver chloride does weird things and becomes less soluble once exposed to light. I had a good reference for that, but it somehow got changed or corrupted. IMO there is some sort of species left on the planchet/coin that undergoes a latent slow change when exposed to air and/or UV light. This whole deal would be great thesis topic for a student in physical or surface chemistry.
All we found is chloride. No sodium, calcium, magnesium or any common mineral found in water.
It could be silver chloride bound to the surface. It can't be silver chloride GROWING on the surface. You'd need more silver chloride.
Silver chloride is photochemical in nature. It doesn't become "less soluble" - and, by the way, where's all this water that it would be dissolved in. Silver chloride when exposed to light reduces to silver metal which is NOT white.
There may well be some species left on the planchet that oxidizes silver over time. It can NOT be HCl or a chloride salt, however.
All comments reflect the opinion of the author, evn when irrefutably accurate.
hloride grow without the introduction of more chlorine.
Why can't it be silver chloride bound to the surface? Also it is known that silver chloride does weird things and becomes less soluble once exposed to light. I had a good reference for that, but it somehow got changed or corrupted. IMO there is some sort of species left on the planchet/coin that undergoes a latent slow change when exposed to air and/or UV light. This whole deal would be great thesis topic for a student in physical or surface chemistry.
All we found is chloride. No sodium, calcium, magnesium or any common mineral found in water.
It could be silver chloride bound to the surface. It can't be silver chloride GROWING on the surface. You'd need more silver chloride.
Silver chloride is photochemical in nature. It doesn't become "less soluble" - and, by the way, where's all this water that it would be dissolved in. Silver chloride when exposed to light reduces to silver metal which is NOT white.
There may well be some species left on the planchet that oxidizes silver over time. It can NOT be HCl or a chloride salt, however.
It would appear to grow if the species on the surface converted to AgCl over time. You wouldn't need to add extra chloride since the chloride would already be there, just not converted to a visible physical form.
And yes according to that article which was written by someone who produced the stuff, silver chloride when exposed to light undergoes a change which renders it less soluble in ammonia solution. It's insoluble in water regardless.
It's not like if you have some silver chloride in a clear jar and put it in sunlight that it goes poof and you end up with silver and chlorine.
er chloride GROWING on the surface. You'd need more silver chloride.
Silver chloride is photochemical in nature. It doesn't become "less soluble" - and, by the way, where's all this water that it would be dissolved in. Silver chloride when exposed to light reduces to silver metal which is NOT white.
There may well be some species left on the planchet that oxidizes silver over time. It can NOT be HCl or a chloride salt, however.
It would appear to grow if the species on the surface converted to AgCl over time. You wouldn't need to add extra chloride since the chloride would already be there, just not converted to a visible physical form.
And yes according to that article which was written by someone who produced the stuff, silver chloride when exposed to light undergoes a change which renders it less soluble in ammonia solution. It's insoluble in water regardless.
It's not like if you have some silver chloride in a clear jar and put it in sunlight that it goes poof and you end up with silver and chlorine.
IT CAN'T BE CHLORIDE. Chloride is a chlorine ion. It could be a chlorine containing species that undergoes an oxidation/reduction reaction, but it can NOT be chloride. HCl is a gas. The other chlorides are solids. A metal chloride, call it MCl can NOT turn Ag into AgCl without another chemical agent to oxidize the silver metal to silver ion.
The photochemical reactions of silver chloride are WELL WELL WELL known as it was used in photography for 100 years.
Silver chloride itself will NOT CHANGE SOLUBILITY. Silver chloride is CHEMICALLY CHANGED into something that is less soluble. The rules governing solubility are also well known for ionic compounds.
I'm wasting my time here.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@BAJJERFAN said: "The scientist isn't there anymore. What he did was done gratis since they normally would charge for it. Also the TPGs use the same compressed air for all coins, no? Why don't they have complaints about water-spotting on other coins? Or do they? [AT LEAST TWO PLACES I WORKED AT DID. That's when we began to filter the air. First with one, then two filters!] Unless it's some sort of mold the contamination in hoses and nozzles left long ago. If water in the compressed air was an issue they would or should have addressed it long ago, unless it is so magical that it affects only silver bullion and nothing else.
Of course coins from the mint don't have spots on them [ACTUALLY THEY DO! Right out of the tube. Additionally, spots were occurring after the coins were graded "perfect." That's why the coins are no longer guaranteed.] but the roundish nature of the dry spots suggests that they were droplets at some point.
Yes, many are droplets. Note that they come in different sizes and concentrations. Additionally, some are large ragged stains. The tiny ones come right off. That's what led us to believe the air hoses were involved.
It's not like if you have some silver chloride in a clear jar and put it in sunlight that it goes poof and you end up with silver and chlorine.
To be clear, the milk spots COULD be silver chloride. But they can not be caused by the presence of silver chloride PRIOR TO THEIR APPEARANCE.
There would have to be another agent present. Possibly bleach. Bleach is capable of oxidizing silver to silver ion, but the chemistry would need to be more complicated to end at silver chloride.
All comments reflect the opinion of the author, evn when irrefutably accurate.
It's not like if you have some silver chloride in a clear jar and put it in sunlight that it goes poof and you end up with silver and chlorine.
To be clear, the milk spots COULD be silver chloride. But they can not be caused by the presence of silver chloride PRIOR TO THEIR APPEARANCE.
There would have to be another agent present. Possibly bleach. Bleach is capable of oxidizing silver to silver ion, but the chemistry would need to be more complicated to end at silver chloride.
There was no oxygen like might be found in bleach which is hypochlorite.
Comments
<< <i>what's the "problem"?
milkspotting happens. live w/ it.
K S >>
Death and $hit both happen too; you want to live with those?:
<< <i>I don't do much with ASE's, but have heard that NGC coins don't spot as often. Check out what differences there are between your slab composition and theirs, and see what the difference is.
I've seen a number of green label PCI slabbed ASE's with absolutely no spots, maybe you should model your plastic after theirs.
idk, food for thought >>
So is there a point in time during which the problem seems to have gotten noticeably worse like in say the last couple of years? Or has it always been something of a low level problem that just never got much air time? seems like you hear more about with recent ASE dated issues than 1986 or 1987 issue coins.
Wouldn't surprise me that the planchets are actually coming from China or India.
<< <i>Since HRH has put significant research into the topic, it would be best to know what is already known and go from there >>
Truer words were never posted.
milk spots cause -
a chemical reaction with AG+ (on the coin) and Cl- (in the air) to form AgCl on the surface of the coin, similar to toning or PVC contamination
it is more prevalent on 99.9% silver coins (ASEs), but also can be found on 90% silver but more noticable or distracting on proof coins with deep mirrors
originally found on the surface but after continued exposure, can etch into the coin like PVC contamination
can be found prestrike, or post strike and can start at any time with the exposure of free Cl-
exposure usually by Cl- in the air and more prevalent near salt water
treatment -
dip in ammonia solution and then neutralize/dilute with dip in distilled water and final dip in acetone
if metal already etched, may leave small pits
if struck into the coin, dips may not get to contaminant
prevention -
after treatment, keep in airtight container
- either wrap in something (like aluminum foil) or have dessicant in container like glass jar
- at this time, slabs are NOT airtight, so additional protection is needed
good luck and practice on some lower valued coins
and remember, if you drink too much of anything (including water), you may die
<< <i>As far as I know NGC and ANACS dont have the milk spotting problem, or at least not to the extent that PCGS does. I'm not the sharpest knife in the drawer but isnt Newport Beach, CA geographically located between the Pacific Ocean and Newport Bay. The salt in the air is so thick you can smell it. When employees come in from outside it's on their clothes and in their hair so any special filtration systems or clean rooms are instantly contaminated. >>
Good point, we had a customer in India who had such an inordinate amount of hardware failures we contracted to have the parts analyzed. Turns out there was so much sulfur dioxide in the air it was corroding the circuit boards. Solution, put in a big air filter. SAE's are 5 nine silver, it would not take much of a contaminate to spot them.
President, Racine Numismatic Society 2013-2014; Variety Resource Dimes; See 6/8/12 CDN for my article on Winged Liberty Dimes; Ebay
<< <i>It's the wash. They can be dipped and rinsed in distilled water, and they would be fine; however, that would make you a coin doctor and the sniffer would catch the dip, so the answer is there is no answer without dipping. >>
I would try boiling a new unspotted coin in distilled water instead of just rinsing.
<< <i>SAE's are 5 nine silver, it would not take much of a contaminate to spot them. >>
SAE's are 3 nine silver. Canadian Maples are 4 nine silver and I see more spotting on them right out of the monster box.
No Way Out: Stimulus and Money Printing Are the Only Path Left
<< <i>since this is the only thread or article about milk spotting that has any PCGS officials posting, other than the January 7, 2008 Coin World article, I will post my theory on cause, treatment and prevention here.
milk spots cause -
a chemical reaction with AG+ (on the coin) and Cl- (in the air) to form AgCl on the surface of the coin, similar to toning or PVC contamination
it is more prevalent on 99.9% silver coins (ASEs), but also can be found on 90% silver but more noticable or distracting on proof coins with deep mirrors
originally found on the surface but after continued exposure, can etch into the coin like PVC contamination
can be found prestrike, or post strike and can start at any time with the exposure of free Cl-
exposure usually by Cl- in the air and more prevalent near salt water
treatment -
dip in ammonia solution and then neutralize/dilute with dip in distilled water and final dip in acetone
if metal already etched, may leave small pits
if struck into the coin, dips may not get to contaminant
prevention -
after treatment, keep in airtight container
- either wrap in something (like aluminum foil) or have dessicant in container like glass jar
- at this time, slabs are NOT airtight, so additional protection is needed
good luck and practice on some lower valued coins
and remember, if you drink too much of anything (including water), you may die >>
I think you have a bit more splainin to do.
It is found on coins in NGC slabs and on coins from new mint tubes too. If it was air borne chloride shouldn't it affect all coins and not just ASEs and shouldn't it affect all ASEs?
How do you explain the appearance as round spots or sometimes irregular shaped spots? If twas airborne the entire coin should be affected. Seems to me it is deposits left after evaporation of a liquid.
<< <i>
<< <i>SAE's are 5 nine silver, it would not take much of a contaminate to spot them. >>
SAE's are 3 nine silver. Canadian Maples are 4 nine silver and I see more spotting on them right out of the monster box. >>
you are correct, my bad. they are .999 fine, I was thinking 99.999 fine, which is 5 ninse but they are 99.9% silver.
BTW -I will add, that I don't own a single SAE that has milk spotted, I have had a couple of hundred, PCGS, mint packaging, proof, non proof. Some I have had since 86.
Retired Coin Shop Owner .
Still Collecting
Love my Grandkids and my German Shepherd Dogs . Kind of like my wifes Cat.
-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-
My sets: [280+ horse coins] :: [France Sowers] :: [Colorful world copper] :: [Beautiful world coins]
-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-
Box of 20
<< <i>Why people slab bullion I will never understand. >>
Well not all of it is created equal and some do more than just stack it in the corner. Plus it provides a revenue stream for our hosts to have enough money to host this forum.
BTW
<< <i>Why people slab bullion I will never understand. >>
Then this ain't your thread....
to clean the coins before encapsulating them, there may condensation in the line and small particles
of water, unseen to the eye, would land on the coin and the end result would be the appearance of milk spots.
I do not know if the TPG's give the coins a blast of air or not before slabbing, it was just the only thing I could
think of since I have had it happen when painting cars using an air compressor. If the condensation is not
out of the line, it will invariably wind up on the car and is noticeable in the final product.
I have seen videos of the US mint using compressed air to clean the coins one last time before encapsulating.
This may be the reason that some of the coins develop spots while still in the OGP, if condensation is in the air line
used to clean the coins.
The video was on one of the cable channels on a program about the US Mint.
I don't recall the name of the episode though.
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots?
I've been told I tolerate fools poorly...that may explain things if I have a problem with you. Current ebay items - Nothing at the moment
<< <i>
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots? >>
They all come back without the spots
<< <i>
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots? >>
same coin no spots for me, sometimes they forget to remove a "dip" tag from the slab (whatever for?) not that the slab gets dipped..lol
<< <i>
<< <i>
<< <i>Plenty of milk spots. I have send several PCGS 70s and NGC 70s for spot review. They all come back without the spots. Both TPGs are good on their guarantees. So I can see why PCGS wants to try to solve this. I wonder if the the solution will be kept secret or shared with NGC? >>
Do "they" come back without spots or, more likely, they send you back an equal coin in an equal slab and keep the original since they can't remove the spots? >>
same coin no spots for me, sometimes they forget to remove a "dip" tag from the slab (whatever for?) not that the slab gets dipped..lol >>
Makes me wonder if the spot is the same as the other milk spots we have heard about or if they finally have a solution for it (pun intended
From what I recall during the ASE heydays of collecting, once the milk spot showed up, it was too late and couldn't be gotten rid of.
Hope they do have a solution
I've been told I tolerate fools poorly...that may explain things if I have a problem with you. Current ebay items - Nothing at the moment
Hoard the keys.
Old Thread Update
Was this reward ever claimed? This was issued over 10 years ago in 2007.
Just ran across this article by Joshua McMorrow-Hernandez while searching for silver eagles in general.
https://coinweek.com/education/coin-grading/ngc/coin-analyst-collectors-crying-milk-spotted-american-silver-eagles/
Cause and solution were provided long ago, but never acknowledged. Production and examination conditions might have changed, so the subject would require complete reexamination.
Rinse the planchet's in oil, synthetic oil, motor oil even vegetable oil will work.
Wisdom has been chasing you but, you've always been faster
Put them in your dinner salad with oil and vinegar dressing....?
...has anyone tried Oreos?...if it works, I’ll take my 50 smackers in Oreo cookies
Who in the HELL is gonna dip 25,000 ASEs?
You realize you're talking to a dead man.
All comments reflect the opinion of the author, evn when irrefutably accurate.
Indeed I do. Was just intended as a comment to the crowd and not a response to the poster. Without rereading the the whole thread [I know it's OLD] there are a lot of old names [Dorkkarl was banned? I did not know that] and a lot of bullchit and speculation.
One thing that PCGS could have done[and maybe did] was simply reholdered a new ASE and sold off the spotted ones instead of spending countless hours trying to conserve them.
One thing I've posted that ALWAYS seems to fall on deaf ears is that it's been said that one can see the spots BEFORE they become visible by looking at it using a halogen flashlight. At this point they can be removed by dipping in EZest. Once visible they are there for good. The spots are silver chloride and silver chloride is NOT soluble in acetone. There may be more than one cause of the spots. Some look white and some are tea colored. Chloride presence suggests that there was a hydrochloric acid wash somewhere in the process that was never properly washed/rinsed off. IIRC the mint started using the HCl wash back in 1921 which probably explains 1921 Morgans and Peace dollars tone differently from earlier Morgans.
Also here is a scanning electron micrograph of the surface of an ASE.
The spots tend to form at the roughest areas of the coin surface.
I have not had a good chuckle for a couple days. Browsing the first couple pages of this moldy oldie fixed that right quick.
@BAJJERFAN said: "The spots tend to form at the roughest areas of the coin surface."
Please clarify. At those powers, the entire surface is rough. Therefore, in order to convince me of the "truth" of your opinion ("The spots tend to form at the roughest areas of the coin surface.") I'd need to see a spot and the area around it. In fact, more than in one place because as the person taking the image to prove your point, it would be possible to choose what area to image - a spot in a really rough area.
What does make sense is that the roughness would be more likely to "trap" chemicals.
IMO many spots on holdered coins are caused by faulty filtering of the air used to blow out the coin and cases.
You can actually see the "vapor" come out of the nozzle.
I thought the canadian mint solved this issue ?
That's not my opinion. It was the opinion/observation of the tech who assisted me in checking out the spots on a silver eagle.
First order of business was to examine the spot using a technique called XPS X-ray Photoelectron Spectroscopy [aka ESCA Electron Spectroscopy Chemical Analysis] with the help of a scientist at the Ames Laboratory. He found only other element besides silver was chlorine.
He also looked at the coin surface with a high magnification microscope and did or had someone do the SEM work. His observation was that droplets remaining on a coin surface tended to accumulate at the rougher areas; a not unexpected conclusion.
You can't filter water out of compressed air. You either need a dryer system to remove it or a chiller of some type to freeze or condense it out. Moisture in compressed air should be essentially like distilled water so if it gets on a coin surface it shouldn't deposit anything. Sometimes if one spills water on something it leaves a lighter looking spot. I'm pretty sure it is not the reason for the spots on ASEs, esp. since they can be spotted right from the mint tube.
As I posted, it makes sense that the spots would occur where something would be more likely to accumulate and trap them.
AFAIK, no TPGS uses "a dryer system to remove it or a chiller of some type to freeze or condense it [water vapor] out." As for this: "Moisture in compressed air should be essentially like distilled water. ** All well and fine except the air goes through hoses and nozzles that can contaminate the air. While everyone knows SE coins come spotted from the mint,I assure you from personal experience (actual TESTS) inside a TPGS** that "virgin" coins will spot with the air hoses!
Finely, the coins from the mint do not have droplets on them. His experiment proves what should be obvious. However, the scientist may wish to do the experiment I recommended on DRY coins with spots.
Not exactly. The Canadian mint solved the issue by coating the coins.
All comments reflect the opinion of the author, evn when irrefutably accurate.
Love the micrograph, but the chemistry doesn't make sense to me.
HCl is a gas at room temperature. HCl is water soluble. So it can't be HCl on the surface that won't wash off. Chloride cannot be on the surface without a counterion. If it's not HCl (a water soluble gas, as mentioned) then it has to be another metal salt. It can't be "invisible" silver chloride because why would the silver chloride grow without the introduction of more chlorine.
All comments reflect the opinion of the author, evn when irrefutably accurate.
So I guess that's the solution then....
The scientist isn't there anymore. What he did was done gratis since they normally would charge for it.
Also the TPGs use the same compressed air for all coins, no? Why don't they have complaints about water-spotting on other coins? Or do they? Unless it's some sort of mold the contamination in hoses and nozzles left long ago. If water in the compressed air was an issue they would or should have addressed it long ago, unless it is so magical that it affects only silver bullion and nothing else.
Of course coins from the mint don't have spots on them, but the roundish nature of the dry spots suggests that they were droplets at some point.
Why can't it be silver chloride bound to the surface? Also it is known that silver chloride does weird things and becomes less soluble once exposed to light. I had a good reference for that, but it somehow got changed or corrupted. IMO there is some sort of species left on the planchet/coin that undergoes a latent slow change when exposed to air and/or UV light. This whole deal would be great thesis topic for a student in physical or surface chemistry.
All we found is chloride. No sodium, calcium, magnesium or any common mineral found in water.
hloride grow without the introduction of more chlorine.
It could be silver chloride bound to the surface. It can't be silver chloride GROWING on the surface. You'd need more silver chloride.
Silver chloride is photochemical in nature. It doesn't become "less soluble" - and, by the way, where's all this water that it would be dissolved in. Silver chloride when exposed to light reduces to silver metal which is NOT white.
There may well be some species left on the planchet that oxidizes silver over time. It can NOT be HCl or a chloride salt, however.
All comments reflect the opinion of the author, evn when irrefutably accurate.
It would appear to grow if the species on the surface converted to AgCl over time. You wouldn't need to add extra chloride since the chloride would already be there, just not converted to a visible physical form.
And yes according to that article which was written by someone who produced the stuff, silver chloride when exposed to light undergoes a change which renders it less soluble in ammonia solution. It's insoluble in water regardless.
It's not like if you have some silver chloride in a clear jar and put it in sunlight that it goes poof and you end up with silver and chlorine.
er chloride GROWING on the surface. You'd need more silver chloride.
IT CAN'T BE CHLORIDE. Chloride is a chlorine ion. It could be a chlorine containing species that undergoes an oxidation/reduction reaction, but it can NOT be chloride. HCl is a gas. The other chlorides are solids. A metal chloride, call it MCl can NOT turn Ag into AgCl without another chemical agent to oxidize the silver metal to silver ion.
The photochemical reactions of silver chloride are WELL WELL WELL known as it was used in photography for 100 years.
Silver chloride itself will NOT CHANGE SOLUBILITY. Silver chloride is CHEMICALLY CHANGED into something that is less soluble. The rules governing solubility are also well known for ionic compounds.
I'm wasting my time here.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@BAJJERFAN said: "The scientist isn't there anymore. What he did was done gratis since they normally would charge for it. Also the TPGs use the same compressed air for all coins, no? Why don't they have complaints about water-spotting on other coins? Or do they? [AT LEAST TWO PLACES I WORKED AT DID. That's when we began to filter the air. First with one, then two filters!] Unless it's some sort of mold the contamination in hoses and nozzles left long ago. If water in the compressed air was an issue they would or should have addressed it long ago, unless it is so magical that it affects only silver bullion and nothing else.
Of course coins from the mint don't have spots on them [ACTUALLY THEY DO! Right out of the tube. Additionally, spots were occurring after the coins were graded "perfect." That's why the coins are no longer guaranteed.] but the roundish nature of the dry spots suggests that they were droplets at some point.
Yes, many are droplets. Note that they come in different sizes and concentrations. Additionally, some are large ragged stains. The tiny ones come right off. That's what led us to believe the air hoses were involved.
To be clear, the milk spots COULD be silver chloride. But they can not be caused by the presence of silver chloride PRIOR TO THEIR APPEARANCE.
There would have to be another agent present. Possibly bleach. Bleach is capable of oxidizing silver to silver ion, but the chemistry would need to be more complicated to end at silver chloride.
All comments reflect the opinion of the author, evn when irrefutably accurate.
There was no oxygen like might be found in bleach which is hypochlorite.