Milk spots How? And why?

[Uksilverstackers]

Thank you Kimchi, that is very interesting 😳

I just found this, which although refers to US coins, maybe other mints use the same process....

The first step in generating coins is the manufacturing of strips of metal with proper thickness. The U.S. Mint purchases these strips, for all coins apart from pennies, from commercial suppliers.)

How Coins are made (US)

[ChrisF]

8 hours 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.

Better off using a silver polish cloth.

[Uksilverstackers]

Here is a much better webpage link below on the processing. The more I read, the more I'm thinking that .9999 Silver will have some of the .0001 attributed to unremoved residue/chemical/ and its this that could cause the White Spots and why it cannot be removed by washing/rinsing as its integral to the constitution of the silver and subsequently leeches out over time.

This page also mentions the use of a X-Ray Spectrometer to analyse the metal constitution of a bar. Here could be a cost implication for the mint in that there may be different grades of .9999 silver. But what do I know...

The webpage goes on to include:

He explains that Allgemeine is one of the biggest European producers of silver semi-finished products like tubes for jewelers, which can easily be transformed to rings, silver sheets and of course blanks, on which the German commemorative coins are struck.

Its near the end of this webpage regarding blanks etc, so scroll through, but its good to read about the processing and what is involved.

Processing into Blanks etc

Ultimately it would appear that good Quality Control at every stage will provide the best blanks using the best processed Silver. That may be why some coins have White Spots and some dont.

So my take on that, is, any Mint that are buying in Blanks/Sheets, are the mercy of the Quality Control/Cost from the company they are purchasing the product from and therefore struggle to do anything about resolving White Spots. To compound the issue, I guess there are also only a few major companies that can provide that level of Process/Refining/Product that they can buy from.

Enjoy 👍😎

[Uksilverstackers]

8 hours 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?

I think we are thinking along the same lines Kimchi 👍😎

[StackemHigh]

Generally thought suggests that spotted coins come from blanks that haven't been cleaned properly before being pressed.  The dry residue on the coin oxides months sometimes years later.  

Perth mint does have a good reputation for quality.  

[Lowlow]

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

Milk spots are inevitable.

 

No, it's just that they won't fix the problem.  It's probably even TRIVIAL for the mints to fix.

No coin I have before 2000 has any milk spots on it, and as far as I know that's true of coins back to Greek and Roman times.  It's only modern coins that have this problem ... because reasons.  Reasons that apparently mints just don't give a F about.  The U.S. Mint claims it has been a problem since 1986 but none of my older eagles have any spots.

The problem, is that most bullion investors don't seem to care that it's a problem ... or they aren't vocal enough about it, or they are and the mint just don't give a damn.  Personally I think it's the last one, but I do know that a lot of bullion investors don't care.  I don't care much but that's mostly because I don't like paying premiums for eagles in the first place.  I DO get angry about the spots ... but NOT because I care, it's because I see so many people who value the appearance of the coins who DO care .. and I think they should get what they want.  It irritates me that a lot of you collect and have to deal with spots on your coins, when there's like absolutely NO REASON for it.  To me it's just a rip in the Universe ... like if people were selling cars but they came with four wheels and only three tires and none of the manufacturers would put a tire on the front passenger side .. .and then acted like it wasn't a problem.  It just irritates me for that reason, because it's so OBVIOUSLY a problem for collectors and nobody cares.

Note to mints everywhere .. can't figure out the milk spotting problem ?  How about just do whatever mints around the whole freaking world did since antiquity up until about 1965 when silver stopped being official currency .. you know, that short period of like THREE THOUSAND FREAKING YEARS when milk spotting wasn't a problem.  That might fix it.

You can almost hear them from the grave ... hey look, we didn't have running water ... but we could make coins without milk spots.

[Lowlow]

I bet that if the President or Prime Minister of any country that has milk spotting problems went to their mints and said "If there are milk spots on our coins next year you're all going to lose your job" ... I bet they'd get fixed.

[Martlet]

1 hour ago, Lowlow said:

No, it's just that they won't fix the problem.  It's probably even TRIVIAL for the mints to fix.

 

That is demonstrably untrue, if it were trivial they'd have fixed it.

[Lowlow]

6 minutes ago, Martlet said:

That is demonstrably untrue, if it were trivial they'd have fixed it.

HAHAHAHAHA what makes you so confident of THAT ??!?!!?

You're trying to apply REASON to a situation where that may not be advisable LOL.

Let me ask you this, I get rounds from private mints and NONE of them have milk spots.

If it's so hard to stop, why don't the rounds I buy have milk spots ?

[Martlet]

4 minutes ago, Lowlow said:

HAHAHAHAHA what makes you so confident of THAT ??!?!!?

You're trying to apply REASON to a situation where that may not be advisable LOL.

Let me ask you this, I get rounds from private mints and NONE of them have milk spots.

If it's so hard to stop, why don't the rounds I buy have milk spots ?

Less pure silver?  Multiple mints afflicted with the same issue, to different degrees, one making a new technology to hide/prevent the problem, unclear what the cause even is, all points to a non-trivial problem. 

[Lowlow]

5 minutes ago, Martlet said:

Less pure silver?  Multiple mints afflicted with the same issue, to different degrees, one making a new technology to hide/prevent the problem, unclear what the cause even is, all points to a non-trivial problem. 

Yeah but see you're even giving evidence for how inept they are.  It's literally something white on the coin ... you think it's that hard to do a chemical analysis of it to see what it is ?  That they don't know what is causing it is just further proof of how little they care about fixing it.  We put people on the moon ... you think they can't figure out how to stop milk spots if they wanted to ?  I mean the milk spots are right there .. they exist in this universe, science can solve this problem LOL.

I think it's pretty obvious that it isn't a problem that they need to "solve" as much as it is a problem they need to stop INTRODUCING with their current process.  It's obvious (to me) that it's something they are doing that private mints aren't doing .. either a chemical they are using, some kind of process they are doing, a detergent they are washing blanks with, or something that private mints don't do, or do differently, or better.

Less pure silver ?  Says 999, I have no reason to think it isn't.

[dicker]

I have a friend who uses VP90 sachets which is used to protect guns from corrosion. Not tried myself but he says it works 

[Tn21]

This looks super impressive

[Lowlow]

2 hours ago, Tn21 said:

This looks super impressive

It really is personal preference.  I watch the video and kind of roll my eyes at the producers.  But to each his/her own.  At least I wish he would stop calling tarnish "dirt" or saying the coins are "dirty" lol.

I like a light tarnish on bullion, it makes it easier to identify.

[Lowlow]

2 minutes ago, Lowlow said:

I like a light tarnish on bullion, it makes it easier to identify.

Or maybe a better way to say that is that I like a bit of tarnish because I just prefer the look of it, and it helps make it easier to identify.  To me a bit of tarnish is just like having some thyme growing over some cobblestones on your walkway, or some ivy growing along brickwork, or some wildflowers haphazardly growing along a curb ... it just looks nice.  But I understand some people just want everything super clean ... a detailed car, marigolds growing in perfect rows, alphabetized blu-ray collection, etc ... that just isn't me.