Milk spots How? And why?

[matrawr]

As the title mentions myself and another member was wondering about milk spots in modern coins and how long has this been an issue?

Anyone knowledgeable on this topic?

Thanks

Mat

[Roy]

https://thesilverforum.com/search/?q="milk spots"&sortby=relevancy&search_in=titles

😀

[fiveshotdon]

Milk spots are inevitable, I didn't know anything about them when I first started stacking and it was a huge disappointment when I started to find them in my collection.

If they bother you I would recommend you don't purchase coins from the Canadian mint. The Perth mint produces coins that generally spot a lot less, exception is the kangaroo. Milk spots are the reason I'm not buying anything except bullion silver coins.

In my experience, coins that I have received capsuled directly from the mint have spotted less (chinese panda, kookabura, koala, britannia 20th anniversary).

 

[Bimetallic]

The Royal Canadian Mint claims to have solved the problem: https://www.mint.ca/store/campaign/Mintshield-7700022

https://www.coinworld.com/news/precious-metals/2018/02/royal-canadian-mint-develops-milk-spot-fix.all.html

[matrawr]

Yes I heard that RCM were doing something to reduce/eliminate it which is good of them I'm not sure if any other mints are doing the same/similar? 

It just came up in conversation whilst talking about older coins and modern coins because I've not known older coins to have them.

[JunkBond]

It was me that has been chatting with @matrawr about this issue and we were wondering if any long term silver collectors could remember when this first became a problem as older coins and minted bars (say pre 1990) seem to be immune..

[terakris]

I have some old silver, early 80's and its spotless, yet i have about 10oz of 2018 silver that's has the dreaded spots, random mints. What I did notice is it seems to spread - most of my stuff is separate in capsules but I do have some in bags/flips too. What i noticed on one of the flips was the milk spot was transferred to the flip as well as being on the coin, which would mean if 2 coins were next to each other its likely the milking would be on both where they touched.

[matrawr]

Thanks @JunkBond you explained it better than I could 😛

2 hours ago, terakris said:

I have some old silver, early 80's and its spotless, yet i have about 10oz of 2018 silver that's has the dreaded spots, random mints. What I did notice is it seems to spread - most of my stuff is separate in capsules but I do have some in bags/flips too. What i noticed on one of the flips was the milk spot was transferred to the flip as well as being on the coin, which would mean if 2 coins were next to each other its likely the milking would be on both where they touched.

So it's like an infectious disease?

[Tingles]

10 minutes ago, matrawr said:

Thanks @JunkBond you explained it better than I could 😛

So it's like an infectious disease?

Fungus? Mould? 

[terakris]

12 minutes ago, matrawr said:

Thanks @JunkBond you explained it better than I could 😛

So it's like an infectious disease?

Not sure what it is exactly, i guess it something in the manufacturing process that reacts over time but it left marks on the clear section of the flip so for instance i wouldnt want to reuse a capsule that had a milky coin in just in case...

[Rgcoins]

Actually I find these milk spots are more common during coins released during Xmas. 

I’m sure during the minting process, the person on the qc line was enjoying a cup of milk, dipping his/her cookies in it. Time to time mistakenly dips a coin into the milk. 

Many theories, Canadian mint tried to explain it in full detail. I do honestly believe my theory has nailed it on the spot

[fiveshotdon]

7 minutes ago, Rgcoins said:

Actually I find these milk spots are more common during coins released during Xmas. 

I’m sure during the minting process, the person on the qc line was enjoying a cup of milk, dipping his/her cookies in it. Time to time mistakenly dips a coin into the milk. 

Many theories, Canadian mint tried to explain it in full detail. I do honestly believe my theory has nailed it on the spot

So does this mean that the coins minted in the UK are not actually milk spots? They are tea spots, for we don't dip cookies in milk, we dip digestives in tea...

[greendragon]

Time for an experiment?

place a pre 1990 unmarked coin in a flip with a milked coin(say a maple) and leave for a year or two

then get back to us with results

[Rgcoins]

32 minutes ago, fiveshotdon said:

So does this mean that the coins minted in the UK are not actually milk spots? They are tea spots, for we don't dip cookies in milk, we dip digestives in tea...

Exactly... no wonder the milk spots styles are different from different mints 

[Uksilverstackers]

I'm guessing if these guys dont know what causes it, who knows.  Or they are making big money by not saying....

NGC Conservation - White Spots

 

Of course could also be tea / coffee spots 😀

[nadiasilver3]

On 15/09/2018 at 15:15, Bimetallic said:

The Royal Canadian Mint claims to have solved the problem: https://www.mint.ca/store/campaign/Mintshield-7700022

https://www.coinworld.com/news/precious-metals/2018/02/royal-canadian-mint-develops-milk-spot-fix.all.html

backyard bullion actually has a video out on this. He says use an eraser a very clean eraser to take off the milk spots. I tried it myself using just a regular mechanical pencil eraser and it worked! as long as you're not against a little smudging, which can be easily taken care of by some hot breath and a soft cloth, then this is a great solution. He does caution that you will be making micro abrasions on the coin and if that bothers you or for collecting then yeah I wouldn't use that method but if it's just for standard bullion by weight then I wouldn't worry about it.

[terakris]

5 hours ago, nadiasilver3 said:

backyard bullion actually has a video out on this. He says use an eraser a very clean eraser to take off the milk spots. I tried it myself using just a regular mechanical pencil eraser and it worked! as long as you're not against a little smudging, which can be easily taken care of by some hot breath and a soft cloth, then this is a great solution. He does caution that you will be making micro abrasions on the coin and if that bothers you or for collecting then yeah I wouldn't use that method but if it's just for standard bullion by weight then I wouldn't worry about it.

I did this on a spade guinea as a test and it left a horrible mark... like a smudged milk spot lol. Still, its only bullion hence why i tried it.

[kimchi]

On 16/09/2018 at 09:40, terakris said:

What I did notice is it seems to spread - most of my stuff is separate in capsules but I do have some in bags/flips too. What i noticed on one of the flips was the milk spot was transferred to the flip as well as being on the coin, which would mean if 2 coins were next to each other its likely the milking would be on both where they touched. 

Very interesting, I had asked about this before (if spotted coins should be 'quarantined') but didn't get any replies. I have full tubes that have all spotted, but is it batches of the same coin, that would seem very likely (?). It'd be interesting to hear if different coins have 'cross contaminated' as @greendragon suggests.

On 15/09/2018 at 20:21, fiveshotdon said:

The Perth mint produces coins that generally spot a lot less, exception is the kangaroo.

This is a pet peeve of mine. Perth obviously know how to generally avoid milk spots, but they take some sort of shortcut on the Roos which mean they are infamous spotters. Could it be the quality of/the treatment/production of the blanks?

[fiveshotdon]

30 minutes ago, kimchi said:

This is a pet peeve of mine. Perth obviously know how to generally avoid milk spots, but they take some sort of shortcut on the Roos which mean they are infamous spotters. Could it be the quality of/the treatment/production of the blanks?

The Roo is a cheap coin, I imagine the manufacturing process is tuned to produce more per hour and at reduced cost, also they don't capsule them so that could be another factor.

[kimchi]

5 minutes ago, fiveshotdon said:

The Roo is a cheap coin, I imagine the manufacturing process is tuned to produce more per hour and at reduced cost, also they don't capsule them so that could be another factor.

All possible yes, though I've had other capsuled premium coins recently that have spotted alas - from smaller Mints generally so they might be buying in blanks from e.g. the Royal Mint. Oriental Brits are better than the standard ones and are capsulated, but there've been spotters on those too.

[Bullionaire]

1 hour ago, terakris said:

I did this on a spade guinea as a test and it left a horrible mark... like a smudged milk spot lol. Still, its only bullion hence why i tried it.

I did the same on the same coin and got a smudge. I just gave the smudge a bit of a buff with a lint free cloth and it went away. 

[greendragon]

we split the atom in 1917. a hundred years on and we dont even know WHAT a milk spot IS let alone how to stop/cure it?

pitiful !

[JunkBond]

I have a theory that they have come about because of the introduction of water based chemicals due to environmental controls in the industry.

Maybe cleaning proceedures used solvent based chemicals prior to this. It would explain why its fairly recent.

[Uksilverstackers]

1 hour ago, JunkBond said:

I have a theory that they have come about because of the introduction of water based chemicals due to environmental controls in the industry.

Maybe cleaning proceedures used solvent based chemicals prior to this. It would explain why its fairly recent.

Yes and I cant see The Royal Mint, melting, forming, milling, rolling, processing and washing the strips of silver that they need to punch blanks. Along with all the manufacturing procedure and regulations involved with that raw processing. I wouldnt be surprised if they buy in the pre washed silver strips from refiners and the mint just carries out the actual pressing and packaging especially given the number of general coins they produce for various countries not just precious metal.

It would be interesting to know for sure.

Has anyone who has done a tour of a mint noticed any processing other than pressing? Maybe the larger mints have that processing facility but maybe the smaller ones do not.

[kimchi]

56 minutes ago, Uksilverstackers said:

Has anyone who has done a tour of a mint noticed any processing other than pressing?

I know someone who had a very special Royal Mint tour (as a dealer), and they were left in tears by the end of it at the way premium coins were treated (no interest in QC etc, apparently the guide got quite nasty when questioned about it,  and someone from senior management had to come down to try to smooth things over - that was for gold).