@Insider2 said: @jmlanzaf said: "Amended to "sometimes don't develop for years. " is that okay?
I cannot imagine planchets are cleaned with WATER. Additionally, imagination does not clean coin planchets or further our knowledge about the Mint operations. I imagine little elves scrub the planchets with...
They aren't cleaned with oil. The detergent is aqueous as is the rinse. The mints themselves suggested that low quality water (i.e. water with contaminants) might be the cause of the spots. As I also said, the Perth Mint refutes that. The Canadian Mint said they don't care what causes the spots. The U.S. Mint said nothing.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@Insider2 said: @BAJJERFAN said: "I can't imagine that the West Point facility doesn't have a proper sized RO reverse osmosis unit set to produce high quality deionized water in bulk quantities."
I cannot imagine planchets are cleaned with WATER. Additionally, imagination does not clean coin planchets or further our knowledge about the Mint operations. I imagine little elves scrub the planchets with...
How about fathom then? What else would you wash them with if it wasn't water? Only the cheapest, most common readily available solvent around. The appearance of the spots suggests that they were the result of a solution/liquid of some sort having evaporated. A person who used to work for the Sunshine mint [one of several suppliers of silver blanks to the U. S. mint] and he said that they got bags of some type of powder [apparently a secret of some sort] to add to the wash water. He has posted that info to these boards. The problem is that nobody who knows the process that is used to either make the blanks and/or after receipt at the mint will come forward and present those processes in detail so that we could figure out for ourselves where the spots might come from. One member here toured the WP facility, but would never divulge enough about the process to be of any value.
If you a Google search you should find a video that talks about removing milk spots from silver leafs. He said that the Canadian mint used borax, but he didn't say in what capacity. I believe that borax is added to silver before smelting to remove impurities. He said that the spots could be removed with "cloudy" ammonia solution and which he promptly demonstrated to be true. However, I don't believe the spots on U. S. coins contain boron. I purchased a graded spotted coin and with the assistance of one of the techs at Ames Laboratory we examined it using a surface analysis technique called ESCA Electron Spectroscopy Chemical Analysis now more commonly known as XPS x-ray photoelectron spectroscopy. The only element that we found other than of course silver was chloride suggesting that the spots are silver chloride. Now how do you suppose that chloride got there? A few years back I had some email contact with the head of QC for the U. S. mint and she said the same thing about the spots being silver chloride. IMO either it's on the blanks when the mint gets them or it's added after that.
Bingo! @BAJJERFAN posted: "...they got bags of some type of powder [apparently a secret of some sort] to add to the wash water.
The "Nit2" just wanted a little clarification from an informed numismatist to correct a mistake posted earlier. Thanks! Planchets are NOT washed in WATER.
@Insider2 said:
Bingo! @BAJJERFAN posted: "...they got bags of some type of powder [apparently a secret of some sort] to add to the wash water.
The "Nit2" just wanted a little clarification from an informed numismatist to correct a mistake posted earlier. Thanks! Planchets are NOT washed in WATER.
Kkathy may have slightly misspoken by just saying water. The rest of us all new what she was talking about. Detergent, by definition, is a water-soluble chemical agent. So, the planchets are washed in a "water solution" and then rinsed in "water". You are picking nits on a grand scale.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@Kkathyl said:
Surface tension is a void of air so what I am saying is the rinse is not cleaning all surfaces. Water contains sodium. It’s the sodium that is left behind. In CT at Spartech Polycast we had to use reverse osmosiss to the water to get as much of contaminant out of water before sending shots of chemical. We used glass and metal for cell casting. Water marks always issue on metal. Hard water soft water always makes difference On beads of water.
In one of the most famous reactions in chemistry, addition of colorless aqueous silver nitrate to an equally colorless solution of sodium chloride produces an opaque white precipitate of AgCl:
Ag + ( aq ) + Cl − ( aq ) ⟶ AgCl ( s )
The solubility product, Ksp, for AgCl in water is 1.77×10−10 at room temperature, which indicates that only 1.9 mg (that is, 1.77 × 10 − 10 m o l of AgCl will dissolve per liter of water. The chloride content of an aqueous solution can be determined quantitatively by weighing the precipitated AgCl, which conveniently is non-hygroscopic, since AgCl is one of the few transition metal chlorides that is unreactive toward water.
AgCl quickly darkens on exposure to light by disintegrating into elemental chlorine and metallic silver. This reaction is used in photography and film.
While above many not describe the reaction that may result in milk spots, key here is, once AgCl formed, it is pretty much insoluble in water and not going to come off the coin, possible even with detergents(?). But, it would also begin to darken as noted as Ag is photosensitive, and break down - does anyone see this with the milk spots over time?
Supporting that it is a Ag compound is that the milk spots aren't found on gold an copper, correct?
Correct. The spots are on the metal and unless your willing to QC out the planchets your done. So is the mints willing to take yield loss in the first part of the process. No. So then they become scientist and try to “fix it” They know the market won’t be able to accept the cost associated with the only fail proof solution.
@Insider2 said: @jmlanzaf said: "Amended to "sometimes don't develop for years. " is that okay?
I cannot imagine planchets are cleaned with WATER. Additionally, imagination does not clean coin planchets or further our knowledge about the Mint operations. I imagine little elves scrub the planchets with...
They aren't cleaned with oil. The detergent is aqueous as is the rinse. The mints themselves suggested that low quality water (i.e. water with contaminants) might be the cause of the spots. As I also said, the Perth Mint refutes that. The Canadian Mint said they don't care what causes the spots. The U.S. Mint said nothing.
In one of the many videos out there showing the minting process, they show that the planchets are rubbed with a little oil on the rims before they are fed into the press. When water washing occurs they may use tap water, but it should be followed up with a deionized water rinse.
@Insider2 said:
Bingo! @BAJJERFAN posted: "...they got bags of some type of powder [apparently a secret of some sort] to add to the wash water.
The "Nit2" just wanted a little clarification from an informed numismatist to correct a mistake posted earlier. Thanks! Planchets are NOT washed in WATER.
Can the water used to prepare the washing solution be called wash water? In my book it can and I'm about as pedantic about that sort of thing as you are.
In one of the most famous reactions in chemistry, addition of colorless aqueous silver nitrate to an equally colorless solution of sodium chloride produces an opaque white precipitate of AgCl:
Ag + ( aq ) + Cl − ( aq ) ⟶ AgCl ( s )
The solubility product, Ksp, for AgCl in water is 1.77×10−10 at room temperature, which indicates that only 1.9 mg (that is, 1.77 × 10 − 10 m o l of AgCl will dissolve per liter of water. The chloride content of an aqueous solution can be determined quantitatively by weighing the precipitated AgCl, which conveniently is non-hygroscopic, since AgCl is one of the few transition metal chlorides that is unreactive toward water.
AgCl quickly darkens on exposure to light by disintegrating into elemental chlorine and metallic silver. This reaction is used in photography and film.
While above many not describe the reaction that may result in milk spots, key here is, once AgCl formed, it is pretty much insoluble in water and not going to come off the coin, possible even with detergents(?). But, it would also begin to darken as noted as Ag is photosensitive, and break down - does anyone see this with the milk spots over time?
Supporting that it is a Ag compound is that the milk spots aren't found on gold an copper, correct?
Best, SH
AgCl is IIRC soluble in ammonia solution. Upon exposure to light it also undergoes a change which makes it insoluble in ammonia. I had a reference to that, but when I went to look for it last night it was gone. Was on the Salt Lake Metals site. FWIW ammonia solution won't remove the spots.
@Insider2 By the way...
me type of powder [apparently a secret of some sort] to add to the wash water.
In one of the most famous reactions in chemistry, addition of colorless aqueous silver nitrate to an equally colorless solution of sodium chloride produces an opaque white precipitate of AgCl:
Ag + ( aq ) + Cl − ( aq ) ⟶ AgCl ( s )
The solubility product, Ksp, for AgCl in water is 1.77×10−10 at room temperature, which indicates that only 1.9 mg (that is, 1.77 × 10 − 10 m o l of AgCl will dissolve per liter of water. The chloride content of an aqueous solution can be determined quantitatively by weighing the precipitated AgCl, which conveniently is non-hygroscopic, since AgCl is one of the few transition metal chlorides that is unreactive toward water.
AgCl quickly darkens on exposure to light by disintegrating into elemental chlorine and metallic silver. This reaction is used in photography and film.
While above many not describe the reaction that may result in milk spots, key here is, once AgCl formed, it is pretty much insoluble in water and not going to come off the coin, possible even with detergents(?). But, it would also begin to darken as noted as Ag is photosensitive, and break down - does anyone see this with the milk spots over time?
Supporting that it is a Ag compound is that the milk spots aren't found on gold an copper, correct?
Best, SH
Yay! Some chemistry!
The reaction would have to be part of a larger sequence of reactions If they were simply forming silver chloride during production, the white spots would be there immediately at the time of production. They may be leaving behind a trace of a chlorine containing compound that over time is forming silver chloride.
All comments reflect the opinion of the author, evn when irrefutably accurate.
@lkeigwin....Good question Lance... and it makes sense that unless MINTSHIELD is a neutralizing solution only, then, as a surface deposition, it could well impede tarnish. Cheers, RickO
@jmlanzaf said: @Insider2 By the way...
me type of powder [apparently a secret of some sort] to add to the wash water.
In one of the most famous reactions in chemistry, addition of colorless aqueous silver nitrate to an equally colorless solution of sodium chloride produces an opaque white precipitate of AgCl:
Ag + ( aq ) + Cl − ( aq ) ⟶ AgCl ( s )
The solubility product, Ksp, for AgCl in water is 1.77×10−10 at room temperature, which indicates that only 1.9 mg (that is, 1.77 × 10 − 10 m o l of AgCl will dissolve per liter of water. The chloride content of an aqueous solution can be determined quantitatively by weighing the precipitated AgCl, which conveniently is non-hygroscopic, since AgCl is one of the few transition metal chlorides that is unreactive toward water.
AgCl quickly darkens on exposure to light by disintegrating into elemental chlorine and metallic silver. This reaction is used in photography and film.
While above many not describe the reaction that may result in milk spots, key here is, once AgCl formed, it is pretty much insoluble in water and not going to come off the coin, possible even with detergents(?). But, it would also begin to darken as noted as Ag is photosensitive, and break down - does anyone see this with the milk spots over time?
Supporting that it is a Ag compound is that the milk spots aren't found on gold an copper, correct?
Best, SH
Yay! Some chemistry!
The reaction would have to be part of a larger sequence of reactions If they were simply forming silver chloride during production, the white spots would be there immediately at the time of production. They may be leaving behind a trace of a chlorine containing compound that over time is forming silver chloride.
@lkeigwin said:
I wonder if MINTSHIELD will impeded toning also.
Lance.
Shield implies a treatment or application of a substance so I expect that it would inhibit toning. Then again it may be permeable to small gaseous molecules.
I bought a roll today - looking forward to receiving them.
I live close to one of the larger Ebay bullion sellers. Stopped by the shop with the eBay auction info in hand. Told me the price was now $5 a roll higher than 20 minutes earlier in the day as prices were spiking (I don't believe this turned out to be true). Plus they wanted to hold my check for 10 days to clear. OR i could pay cash, OR I could pay 3% more credit/paypal. They save shipping cost and handling. I walked.
Later this afternoon, their Ebay price dropped $5 a roll from the early morning price, so I pulled the trigger. Paid via Paypal and they pay shipping for a 10 mile ride. We will see how long it takes to deliver.
Even though I got jerked around, I ended up getting a better deal because I walked. I also learned a lesson - never go to the shop in hopes of instant delivery. So I'll simply buy on line in the future.
And yes, they didn't advertise the Mint Shield feature - and didn't mention in while i was in the store.
“In matters of style, swim with the current; in matters of principle, stand like a rock." - Thomas Jefferson
I received a roll of 25 of the silver maple incuse today.
They have a Mint tape seal but it was broken. Normally I would leave it in that state but I decided to look. The first coins I looked at have blemishes on the cheek of the queen. I don’t know if that is milk spotting or another issue but it is obvious and unsightly. I contacted the well-known seller and I’m seeking a resolution.
I will keep you all updated.
Thanks for feedback, I requested a refund and return of the roll as the un-sealed condition causes me to wonder about pre-searching.
I have seen Maples in much better condition that the majority of these in the roll. Back to rounds.
Well, a very professional Shawntee called me and said they would send a pre paid label or offer an exchange, as I want this roll.
And I read this coin is also treated with the new anti-spotting method, so...
Comments
They aren't cleaned with oil. The detergent is aqueous as is the rinse. The mints themselves suggested that low quality water (i.e. water with contaminants) might be the cause of the spots. As I also said, the Perth Mint refutes that. The Canadian Mint said they don't care what causes the spots. The U.S. Mint said nothing.
All comments reflect the opinion of the author, evn when irrefutably accurate.
How about fathom then? What else would you wash them with if it wasn't water? Only the cheapest, most common readily available solvent around. The appearance of the spots suggests that they were the result of a solution/liquid of some sort having evaporated. A person who used to work for the Sunshine mint [one of several suppliers of silver blanks to the U. S. mint] and he said that they got bags of some type of powder [apparently a secret of some sort] to add to the wash water. He has posted that info to these boards. The problem is that nobody who knows the process that is used to either make the blanks and/or after receipt at the mint will come forward and present those processes in detail so that we could figure out for ourselves where the spots might come from. One member here toured the WP facility, but would never divulge enough about the process to be of any value.
If you a Google search you should find a video that talks about removing milk spots from silver leafs. He said that the Canadian mint used borax, but he didn't say in what capacity. I believe that borax is added to silver before smelting to remove impurities. He said that the spots could be removed with "cloudy" ammonia solution and which he promptly demonstrated to be true. However, I don't believe the spots on U. S. coins contain boron. I purchased a graded spotted coin and with the assistance of one of the techs at Ames Laboratory we examined it using a surface analysis technique called ESCA Electron Spectroscopy Chemical Analysis now more commonly known as XPS x-ray photoelectron spectroscopy. The only element that we found other than of course silver was chloride suggesting that the spots are silver chloride. Now how do you suppose that chloride got there? A few years back I had some email contact with the head of QC for the U. S. mint and she said the same thing about the spots being silver chloride. IMO either it's on the blanks when the mint gets them or it's added after that.
Bingo! @BAJJERFAN posted: "...they got bags of some type of powder [apparently a secret of some sort] to add to the wash water.
The "Nit2" just wanted a little clarification from an informed numismatist to correct a mistake posted earlier. Thanks! Planchets are NOT washed in WATER.
Kkathy may have slightly misspoken by just saying water. The rest of us all new what she was talking about. Detergent, by definition, is a water-soluble chemical agent. So, the planchets are washed in a "water solution" and then rinsed in "water". You are picking nits on a grand scale.
All comments reflect the opinion of the author, evn when irrefutably accurate.
W> @RogerB said:
I think you mean XRF?
Best, SH
From Wikipedia:
While above many not describe the reaction that may result in milk spots, key here is, once AgCl formed, it is pretty much insoluble in water and not going to come off the coin, possible even with detergents(?). But, it would also begin to darken as noted as Ag is photosensitive, and break down - does anyone see this with the milk spots over time?
Supporting that it is a Ag compound is that the milk spots aren't found on gold an copper, correct?
Best, SH
Correct. The spots are on the metal and unless your willing to QC out the planchets your done. So is the mints willing to take yield loss in the first part of the process. No. So then they become scientist and try to “fix it” They know the market won’t be able to accept the cost associated with the only fail proof solution.
Best place to buy !
Bronze Associate member
In one of the many videos out there showing the minting process, they show that the planchets are rubbed with a little oil on the rims before they are fed into the press. When water washing occurs they may use tap water, but it should be followed up with a deionized water rinse.
Can the water used to prepare the washing solution be called wash water? In my book it can and I'm about as pedantic about that sort of thing as you are.
AgCl is IIRC soluble in ammonia solution. Upon exposure to light it also undergoes a change which makes it insoluble in ammonia. I had a reference to that, but when I went to look for it last night it was gone. Was on the Salt Lake Metals site. FWIW ammonia solution won't remove the spots.
@Insider2 By the way...
me type of powder [apparently a secret of some sort] to add to the wash water.
Yay! Some chemistry!
The reaction would have to be part of a larger sequence of reactions If they were simply forming silver chloride during production, the white spots would be there immediately at the time of production. They may be leaving behind a trace of a chlorine containing compound that over time is forming silver chloride.
All comments reflect the opinion of the author, evn when irrefutably accurate.
APMEX has 2018 MintShield™ Silver Maple Leafs
https://www.apmex.com/category/90851/2018-mintshield-silver-maple-leafs
I am tempted to buy a few of these and put them back and see if they spot or not,,,,,,, I sure have had plenty of Silver Maples spot in the past.
I wonder if MINTSHIELD will impeded toning also.
Lance.
@lkeigwin....Good question Lance... and it makes sense that unless MINTSHIELD is a neutralizing solution only, then, as a surface deposition, it could well impede tarnish. Cheers, RickO
That would seem to be the case.
Shield implies a treatment or application of a substance so I expect that it would inhibit toning. Then again it may be permeable to small gaseous molecules.
Anyone buy any of these yet??
https://coinweek.com/bullion-report/apmex-offers-mintshield-protected-silver-maple-leafs-royal-canadian-mint/
You know what's a little odd? I don't see ANYONE advertising the Mintshield technology on eBay.
All comments reflect the opinion of the author, evn when irrefutably accurate.
I bought a roll today - looking forward to receiving them.
I live close to one of the larger Ebay bullion sellers. Stopped by the shop with the eBay auction info in hand. Told me the price was now $5 a roll higher than 20 minutes earlier in the day as prices were spiking (I don't believe this turned out to be true). Plus they wanted to hold my check for 10 days to clear. OR i could pay cash, OR I could pay 3% more credit/paypal. They save shipping cost and handling. I walked.
Later this afternoon, their Ebay price dropped $5 a roll from the early morning price, so I pulled the trigger. Paid via Paypal and they pay shipping for a 10 mile ride. We will see how long it takes to deliver.
Even though I got jerked around, I ended up getting a better deal because I walked. I also learned a lesson - never go to the shop in hopes of instant delivery. So I'll simply buy on line in the future.
And yes, they didn't advertise the Mint Shield feature - and didn't mention in while i was in the store.
“In matters of style, swim with the current; in matters of principle, stand like a rock." - Thomas Jefferson
My digital cameo album 1950-64 Cameos - take a look!
And yes, they didn't advertise the Mint Shield feature - and didn't mention in while i was in the store.
Only been in the public eye for barely a week.
Yes, but you'd think they'd be using it for the marketing purpose for which it was designed.
All comments reflect the opinion of the author, evn when irrefutably accurate.
OK.....the real solution to milk spots is not to view your coins while eating a bowl of cereal...........
Pete
.
Nick them and they will tarnish if the skin is broken?
I received my roll of 25 2018 silver Maple Leafs today. Looked them over and there were zero spots anywhere.
Let's see how they fare over time. I'll try to remember to look at them every 6 months or so...
“In matters of style, swim with the current; in matters of principle, stand like a rock." - Thomas Jefferson
My digital cameo album 1950-64 Cameos - take a look!
someone with skills needs to try an AT experiment on one
I'd sacrifice one for the cause. What should I use to tone it? A Taco Bell napkin sounds reasonable. Technically not AT, but could be interesting.
“In matters of style, swim with the current; in matters of principle, stand like a rock." - Thomas Jefferson
My digital cameo album 1950-64 Cameos - take a look!
I have no skills
Perhaps someone can PM with ideas
I received a roll of 25 of the silver maple incuse today.
They have a Mint tape seal but it was broken. Normally I would leave it in that state but I decided to look. The first coins I looked at have blemishes on the cheek of the queen. I don’t know if that is milk spotting or another issue but it is obvious and unsightly. I contacted the well-known seller and I’m seeking a resolution.
I will keep you all updated.
Wash one with acetone or charcoal starter to remove any lacquer and tone that too.
Many Australian and Canadian coins come with hairlines and contact marks on the Queen's cheek. A real shame.
We handle many monster boxes of Canadian Maple Leafs, you would be hard pressed to find a tube that did not contain rounds with out milk spots.
all around collector of many fine things
Thanks for feedback, I requested a refund and return of the roll as the un-sealed condition causes me to wonder about pre-searching.
I have seen Maples in much better condition that the majority of these in the roll. Back to rounds.
Well, a very professional Shawntee called me and said they would send a pre paid label or offer an exchange, as I want this roll.
And I read this coin is also treated with the new anti-spotting method, so...
So, after hearing that Canada has solved the Milk Spot problem I am think about getting a few.
Maple Leafs come in many different varieties.
My question is ,,,,, are all 2018 Maple Leafs varities treated with this Mint Shield process?