New information on the source of milk spots and hazing

[mmissinglink]

bron any chance you can comment on what happened to the testing that was conducted by perth mint back in Jan? Has the removal of particles assisted with less milk spots?

Yes, in fact Bron, if you could, please tell us what specifically the Perth Mint has learned in the months and years that the milk spot problem has been raised as an issue. I'm a relatively new collector (3 years) but those who have been collecting silver coins for years tell me that the issue of milk spots is not just a 2015 problem but has been an issue raised years ago.

What specifically has the Perth Mint ruled out as not causes of milk spots development as a result of newer minting procedures (which appear to be the culprit)?



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[Miloman]

Yeah no worries I am a big boy that can both take it and dish it out.

Sorry but I find the whole fiasco so incredulous and stand by every single comment that I've made.

I want to reiteration what I've said at the risk of sounding like a broken record.

I don't, and many others I've spoken to, believe for a second (lest massive incompetence) that PM and the people there don't know what causes the milk spots, not for a millisecond, I've poured enough of it. Silver doesn't milk spot. Also I've asked about it with the right people. It's the processing, anyone involved in the industry knows that.

Also now the cost to us the consumer. Think for a moment how this has affected us...

We buy coins vs. bars for a reason, we pay a high premium and get gouged by local dealers compared to foreign countries who can purchase OUR NATIONAL coins cheaper than we can.

We spend LOTS and LOTS of money on Perth Mint product proudly displaying our nations heritage. The coins do increase in value because they are limited in production and are meant to be of high quality. Perth mint has loyal customers just look at the lunar series.

So people spend their hard earnt dollars on these coins purchasing from dealers and the secondary market only to have them milk spot and therefore lose virtually all premium on the coin. So we lose money, not Perth Mint. How would you feel? Watching your coin milk spot and the fault rests solely on PERTH MINT not the consumer. Don't we have a right to be upset.

The problem has been sustained and for an extraordinarily long time.

Now I get that you are not technically competent in that area, but doesn't mean that others can't see the issue for what it is. I'll give you a simple analogy...

A truck drives into a tunnel and gets stuck about 3/4 of the way into the tunnel, it is too high. Service men block the road. Police attend and a great number of experts, they take photos of the scene... this goes on for hours and they discuss how they are going to remove the truck. No one has any good solutions. A little 5 year old boy tugs and exclaims "I know how to fix it it!". The police says "the experts know what they are doing" and dismisses the little armchair of a child. The little boy walks away saying "if they only let some of the air out of the tyres, they could just reverse it out".

The most educated people I know are very happy to entertain solutions to problems and have the patience to listen. I could give you a litany of how many things in the world we have that have come from people who weren't considered experts. So please do not be so quick to dismiss armchairs, there many be a valuable lesson in that.

 

[Gatito Bandito]

I don't, and many others I've spoken to, believe for a second (lest massive incompetence) that PM and the people there don't know what causes the milk spots, not for a millisecond, I've poured enough of it. Silver doesn't milk spot. Also I've asked about it with the right people. It's the processing, anyone involved in the industry knows that.

I'd reckon at least a few peeps at most if not all major mints already know -- and don't publicly advertise that. Probably not even internally.


If they were to back out on that particular incriminating process(es), I'm guessing they would no longer be getting all those 69s & 70s from the major TPGs.


I dunno.. I'd probably rather have a spot-free 67 than a spotted-up 70.

 

[SpacePete]

I dunno.. I'd probably rather have a spot-free 67 than a spotted-up 70.

Hallelujah! It just seems like a corruption of the grading process if spotted coins can be rated so highly.

 

[Miloman]

I dunno.. I'd probably rather have a spot-free 67 than a spotted-up 70.

Hallelujah! It just seems like a corruption of the grading process if spotted coins can be rated so highly.

It doesn't work like that SP. The spots develop after the grading. It appears to be really straight forwards despite the double talk we have been hearing, the solution oxidises and the -Cl component of the solution bonds with the silver Ag thus forming the AgCl (milk spot).

The mints are far as I am concerned aren't being honest or straight forwards.

They are heavily invested and change costs money. They are feeding us garbage about air borne impurities thinking that we're all stupid. It's actually insulting. Really insulting and makes them look like the bunch of (insert expletive) that they are.

Have I mentioned how much I dislike those that take advantage of others? The mint is responsible for the fiasco undoubtedly.

They deserve all the lambasting they get.

 

[Miloman]

Just thinking that they are using hydrochloric acid to get the -Cl component to form the AgCl milk spot, seems logical.

Anyway regardless they are treating their customers as though we're stupid. Very annoying.

 

[kramer]

Why doesn't the mint take these faulty products back, destroy the original and replace them? Consumer laws should protect buyers from this. They could even melt them and use them in their pool stock in bar form / working capital.. I can only imagine the cost to the business if these milk spots continue. We're in a modern country in 2015 and this absolutely should not be happening. Pm's processes obviously need changing. If the cost to change is less than the cost to ignore they will just ignore the issue. Good on you miloman for saying what others are thinking. My 2c

 

[barsenault]

I dunno.. I'd probably rather have a spot-free 67 than a spotted-up 70.

Hallelujah! It just seems like a corruption of the grading process if spotted coins can be rated so highly.

It doesn't work like that SP. The spots develop after the grading. It appears to be really straight forwards despite the double talk we have been hearing, the solution oxidises and the -Cl component of the solution bonds with the silver Ag thus forming the AgCl (milk spot).

The mints are far as I am concerned aren't being honest or straight forwards.

They are heavily invested and change costs money. They are feeding us garbage about air borne impurities thinking that we're all stupid. It's actually insulting. Really insulting and makes them look like the bunch of (insert expletive) that they are.

Have I mentioned how much I dislike those that take advantage of others? The mint is responsible for the fiasco undoubtedly.

They deserve all the lambasting they get.

You do understand this right Bron? The PM deserves all the lambasting you are getting.

 

[Northerncoins]

I read somewhere that they started using this "solution" as a lubricant to prolong the life of the dies, but apparently the side effect is some random milk spotting. Cant seem to find the website that I read it on atm.

 

[mtforpar]

As someone who deals quite a bit in graded coins I can confirm that many of the spots develop after the coin is graded. I personally have about 100 coins at the moment with this problem. It is pretty disheartening to invest in a graded coins in the $200 - $500 range to only have its value destroyed by spot development.

I will add though that this phenomenon is not limited to the Perth Mint. I also have coins from Canada, Germany, China, UK, and Mexico that have spot development after slabbing. IMHO it has the potential to devastate the hobby as once you are burned you are much more leery of investing at that level. It can be quite deflating to a collections value and in turn to the collectors enthusiasm.

 

[MasterID]

I think some law suits against the Mints for producing inferior and flawed products and passing off as premium proof coins.
Just need a winning case with a huge fine and the Mints will start weighing the penalty and producing spot free items.

 

[silverzman]

Geiger - NO MORE MILK SPOTS OR TARNISHING!!!!OMG

https://www.geiger-edelmetalle.de/shop_content.php/language/en/coID/4000/content/Arche-Noah/nav/85

The packaging of the coins

The Noah's ark coins are packed in tubes per 20 coins and are surrounded by protective precious gas, wich prevents the tarnishing and the emeging of milk stains" on the precious metal. As long as the sealing is not broken, your investment coins are protected.
The 1oz coin is now delivered in clear tube to guarantee this.

If you never look you are safe!!

 

[Miloman]

After sleeping on it... Hit JACKPOT I think.

Ammonia Chloride 99% certain. Just did a google on it.

Ammonium chloride is used as a flux in preparing metals to be tin coated, galvanized or soldered. It works as a flux by cleaning the surface of workpieces by reacting with the metal oxides at the surface to form a volatile metal chloride. For this purpose, it is sold in blocks at hardware stores for use in cleaning the tip of a soldering iron and can also be included in solder as flux.

I am 10000% certain that the mints are treating us contemptuously.

It was the CL component... it's also produced in conjugation with HCl so was kinda of the right track... just needed to think about it.

 

[Miloman]

Ammonium chloride, an inorganic compound with the formula NH4Cl, is a white crystalline salt, highly soluble in water.

Anyone still believe the mints aren't lying to us?

 

[Miloman]

You know what really got to me? Was when we were told it's not the way the coins are processed. At that point you just can't take anything seriously, it's all spin.

Then we had it's the "air borne particulates" story.... with this...

... they don't have a definative answer beyond semi-conductor style clean rooms which would push the cost so high that we wouldn't sell anything.

Unbelievable right?! Silver milking over air borne particulates?

 

[Miloman]

Perhaps I am overestimating the intelligence of others...?

 

[MasterID]

Singapore Mint minting process, there is a stage (at 2:58) where the coin is dipped into a "AG Passivation".

https://vimeo.com/17076333

 

[Gatito Bandito]

Unbelievable right?! Silver milking over air borne particulates?

I honestly couldn't say either way, but I think there may be a possibility that, in at least some cases, airborne particulates could potentially be a catalyst, of sorts, in planting the seed of a milk-spot -- when other certain conditions are already present.


However, the reason why they would need a clean-room these days, is for the same reason that they *didn't* need a clean-room back 100 years ago, when milk-spotting didn't exist in the coin world..

They are doing something today that they did not do back then!


Of course, if today's mints drop that particular process? Oopsie! There goes all those high grades..

And along with them, decades of minting "advances" down the toilet.


Again, I'll happily take a spot-free MS67 over an unattractively-spotted MS70.

Buying the coin -- not the slab..

 

[Northerncoins]

Its the "Lube" Its all about the cost savings.... :/


"Nanotribology Application in the Coining Industry (II)Optimization of Lubricant Film Formation on Blanks*

ABSTRACT A new method has been developed to lubricate metal coin blanks during the coin production process. The lubricant is formed on the metal surfaces as a monomolecular film during burnishing, which provides an exceptional combination of chemical and tribological environments needed to promote reaction. Laboratory-scale burnishing simulations combined with surface analysis indicated the composition and nature of the films formed. A comparison of reactions on metal surfaces with and without burnishing confirmed the importance of the tribochemical process to the successful lubrication of the blanks.

Implementation of this lubrication procedure to production lines has improved the surface quality of the coins and tripled the die life, resulting in considerable cost savings.

http://www.researchgate.net/publica...zation_of_Lubricant_Film_Formation_on_Blanks*

Burnishing

Burnishing is used to make the surface of the blanks brighter, remove any discolouration and in some cases apply a minute amount of lubricant to assist in coining. This is carried out in a Burnishing Machine that tumbles the blanks amongst a mixture of small steel balls and ceramic media combined with special chemicals, which etch and polish the surface. After burnishing, the blanks pass through a hot air drier. The annealed, burnished and dried blanks are stored ready for coining.

Coining

http://www.ramint.gov.au/designs/products/circulating.cfm

 

[mmissinglink]

Its the "Lube" Its all about the cost savings.... :/


"Nanotribology Application in the Coining Industry (II)Optimization of Lubricant Film Formation on Blanks*

ABSTRACT A new method has been developed to lubricate metal coin blanks during the coin production process. The lubricant is formed on the metal surfaces as a monomolecular film during burnishing, which provides an exceptional combination of chemical and tribological environments needed to promote reaction. Laboratory-scale burnishing simulations combined with surface analysis indicated the composition and nature of the films formed. A comparison of reactions on metal surfaces with and without burnishing confirmed the importance of the tribochemical process to the successful lubrication of the blanks.

Implementation of this lubrication procedure to production lines has improved the surface quality of the coins and tripled the die life, resulting in considerable cost savings.

http://www.researchgate.net/publica...zation_of_Lubricant_Film_Formation_on_Blanks*

Burnishing

Burnishing is used to make the surface of the blanks brighter, remove any discolouration and in some cases apply a minute amount of lubricant to assist in coining. This is carried out in a Burnishing Machine that tumbles the blanks amongst a mixture of small steel balls and ceramic media combined with special chemicals, which etch and polish the surface. After burnishing, the blanks pass through a hot air drier. The annealed, burnished and dried blanks are stored ready for coining.

Coining

http://www.ramint.gov.au/designs/products/circulating.cfm

Can anyone who has an institutional e-mail send me the full text of the first article from above ( http://www.researchgate.net/publica...zation_of_Lubricant_Film_Formation_on_Blanks* )? You can send it to me via PM.


Thanks.




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