The myth of milk spotting.

Russ

A lot of members around here seem to think that milk spots develop on a coin because of an improper dip or conservation attempt. This is NOT what causes them. A bad dip will emerge either as water spotting - which is not the same thing as milk spots - or as brown toning, or golden toning. This toning can be streaky or uniform. Water spotting is translucent and can be corrected, milk spots are opaque and generally cannot be corrected.

The milk spotting can happen while coins are still in mint sealed sets, or it can emerge on the coins after a period of time once removed from the sets. The nature of the spotting is the same in either case, which makes it logically clear that it is related to mint produced surface contaminants.

No coin I have dipped or had conserved at NCS has ever had these spots emerge after holdering. Plenty of undipped examples have.

Russ, NCNE

clw54

Some of my proof sets I've had for years are developing milk spots.

meos1

There has also been plenty of discussion about the milk spots resulting from an incomplete rinse following the planchet wash at the MINT. So it is possible this results from activity at the mint. On thing is for sure it does not come from dipping.

Dan

RobJ

<< <i>A lot of members around here seem to think that milk spots develop on a coin because of an improper dip or conservation attempt. This is NOT what causes them. A bad dip will emerge either as water spotting - which is not the same thing as milk spots - or as brown toning, or golden toning. This toning can be streaky or uniform. Water spotting is translucent and can be corrected, milk spots are opaque and generally cannot be corrected.

The milk spotting can happen while coins are still in mint sealed sets, or it can emerge on the coins after a period of time once removed from the sets. The nature of the spotting is the same in either case, which makes it logically clear that it is related to mint produced surface contaminants.

No coin I have dipped or had conserved at NCS has ever had these spots emerge after holdering. Plenty of undipped examples have.

Russ, NCNE >>



Thank you Mr Russ, now I fully understand.

topstuf

I have a proof Kennedy half with an AWFUL milk spot just below the part in his hair. I have tried EVERYTHING. What else can I try?

VAMs4U2BuyHere

Russ, Do you rinse with distilled water after dipping and do you use acetone at any point during coin prep?

Craton

Can NCS remove those thick milk spots off of proof coins? No dip I have ever done has been able to touch them.

Russ

I only use acetone for PVC removal and, yes, I use distilled water as part of the process.

Russ, NCNE

Russ

<< <i>Can NCS remove those thick milk spots off of proof coins? >>



No, but they sometimes can reduce them enough to make a difference in grade and eye appeal. I wish I knew how, because I've never been able to make a dent in them.

Russ, NCNE

JRocco

Hey Russ, do you have any pics on your drive of coins showing milk spots and coins showing water spots so some here who may not know the difference can see the difference.

nankraut

Just an observation here: It sometimes amazes me how much information/effort Russ contributes to this forum. This thread is yet another example of that. THANKS Russ!

Russ

<< <i>Hey Russ, do you have any pics on your drive of coins showing milk spots and coins showing water spots >>



These are milk spots:





I don't have any pictures of water spotting handy.

Russ, NCNE

dtkk49a

Can someone post a pic of milk spots ?

nolimitz

I wish I had a cheap milk spotted coin to take to work and get a chem analysis on an EDS/EDX SEM.
Might be quicker than some genuis hired by PCGS.

dtkk49a

We hit enter at the same time. Thanks

lathmach

<< <i>I have a proof Kennedy half with an AWFUL milk spot just below the part in his hair. I have tried EVERYTHING. What else can I try? >>



I'll tell you the secret to removing it, but you must promise not to tell anyone.
Use a #2 pencil eraser and rub the spot with it. It will actually "erase" the milk spot.
Please do't tell anyone this secret. The number of proof 70's created will over saturate the market if too many people learn this technique.

Ray

JRocco

Thanks Russ, I am used to seeing milk spotting on coins like your second example, but that first coin really got a double dose. Looks like they were both nice coins once-BUMMER.

Russ

Here's another example from one of my early (pre-dipping) submissions:



That coin was spot free and pristine when it went in. Six months later, that's what it looked like.



<< <i>but that first coin really got a double dose. >>



That one came from the proof set looking like that. Unfortunately, it's a very common problem with the Accented Hair variety - much more so than the regular coin.

Russ, NCNE

WWW

I wish I had a cheap milk spotted coin to take to work and get a chem analysis on an EDS/EDX SEM.

Careful. Steve Appleton has been known to lurk here. (For those outside of Boise,
he's the CEO of a huge semi-conductor manufacturing company and nolimitz's boss.)

Milk spots remind me of some biology experiments involving Petri dishes and bacteria.
It's odd how these nasty little things show up once they are re-exposed to air.

TOMCATTOM

But if I dip my coins, won't the Rainbow toning come off my Morgans?

dpoole

Great discussion.

So what is the haze that invades lots of cam proofs, like this one? Is it the same problem of planchet prep?

(Edited to add: the haze has formed in the original Mint packaging)

Russ

<< <i>So what is the haze that invades lots of cam proofs, like this one? Is it the same problem of planchet prep? >>



It could be prep, but it could also be a packaging issue. If you store a proof coin in a vinyl flip it can sometimes develop haze very similar to that encountered in coins still in sets. That type of problem is easily correctable, though.

Russ, NCNE

XXX

<< <i>

<< <i>So what is the haze that invades lots of cam proofs, like this one? Is it the same problem of planchet prep? >>



It could be prep, but it could also be a packaging issue. If you store a proof coin in a vinyl flip it can sometimes develop haze very similar to that encountered in coins still in sets. That type of problem is easily correctable, though.

Russ, NCNE >>



So how would one correct a problem of haze like you discussed? I have several proof cons which have haze but are otherwise great coins? Thanks, Walt

ccr

Here`s a couple Brown Ikes I have. One has really nice tone and the other heavy hazing.

Cameonut

Excellent post Russ!
You did a great job of explaining milk spots - your explanation fits my experience exactly.

I am going to look for a milk spotted coin to donate to nolimitz for analysis. Knowing what the spots are is the first step in determining a possible removal process. (the only milk spotted coin I have is cooped up in a 59 Franklin holder in 5 ultracam). I seem to remember reading somewhere that milk spots are thought to be cream of tarter that was used in planchet processing.

I ran into a run of light cameo 1962 Franklins with lots of spotting - some were milk spots. I did an experiment and I am happy to report that NCS was successful in removing most of the spotting, but not all. This did improve the eye appeal of the coins quite significantly.
Cameonut

Cameonut

With regard to haze, I have been successful in removing it with MS70. I cut the MS70 with three parts of water because it is too strong straight from the bottle. Get a set of those blue plastic tongs to hold the coin as the MS70 solution is very slippery - you stand a good chance of dropping the coin. Apply the solution very carefully with a cotton swap. Use very light pressure to remove the haze and rinse extremely well. If you do not rinse well, the trace MS70 will re-haze the coin in time.

Keep in mind the MS 70 may also remove light toning as well.

keets

Milk Spots are for the most part impossible to remove totally because they are essentially a part of the coins surface. a more correct term to describe them and to help others understand their nature might be "struck through" since they seem to be the result of an improper rinse at the point of planchet preperation. since there is a film on the planchet surface when the planchet is struck, it becomes embedded in the surface. this was primarily a problem with Proof coins and seemed to end in the early 1970's when the mint made some much needed improvements to their process and QA. dipping and/or conservation by NCS can greatly minimize milk spots, but there is usually a "shadow" left or a faintly visible remnant.

dpoole---------the haze on that Ike is a result of the packaging used by the Mint. very common, happenbs to form on almost all of the coins left in the original packaging.

Coinhusker1

<< <i>No coin I have dipped or had conserved at NCS has ever had these spots emerge after holdering. Plenty of undipped examples have.

Russ, NCNE >>



This is what I meant by "improperly conserved" when I posted in the other thread about the spotted ASEs. Given the risk of milk spots appearing on any proof coin, it seems to me that ALL proof coins taken out of mint packaging should be conserved (i.e. dipped) before submitting.

Hoot

Keets provided the correct information - thanks Al.

I've had milk spots worked on by NCS for a business strike commem. They were able to reduce the spots but not remove them, and there were clearly minor flaws left in the surface of the coin. It made the coin a bit more eye appealing, which was worth it to me, but the experience demonstrated clearly to me the struck-through nature of the spots.

Hoot

Boom

Great Thread

CoinHusker

Thanks for a great thread and discussion! Even though it sounds as though I've expereinced irrepairable damage to 40% of my slabbed SAE set, the information I've gotten has helped to offset that loss. Thanks again!

Jcarney

<< <i>The milk spotting can happen while coins are still in mint sealed sets, or it can emerge on the coins after a period of time once removed from the sets. >>



Emerge is the correct word. Milk spots are a mint created imperfections caused by contaminants on the planchet after being cleaned and rinsed. The contaminants aren't completely rinsed away and are subsequently struck into the coin. They're permanent and cannot be rinsed away with a dip.

19Lyds

ttt

Shamika

<< <i>A bad dip will emerge either as water spotting - which is not the same thing as milk spots - or as brown toning, or golden toning. This toning can be streaky or uniform. >>

It's worth noting that streaky toning DOES NOT always mean the coin was dipped. Poor alloy mix can sometimes be seen as streaky brown or gold toning as well.

ProofRainbowRoosevelt

More ugly milk spots.

MikeInFL

<< <i>A lot of members around here seem to think that milk spots develop on a coin because of an improper dip or conservation attempt. This is NOT what causes them. A bad dip will emerge either as water spotting - which is not the same thing as milk spots - or as brown toning, or golden toning. This toning can be streaky or uniform. Water spotting is translucent and can be corrected, milk spots are opaque and generally cannot be corrected.

The milk spotting can happen while coins are still in mint sealed sets, or it can emerge on the coins after a period of time once removed from the sets. The nature of the spotting is the same in either case, which makes it logically clear that it is related to mint produced surface contaminants.

No coin I have dipped or had conserved at NCS has ever had these spots emerge after holdering. Plenty of undipped examples have.

Russ, NCNE >>



Very good post Russ, thanks for taking the time to set the record straight. For those of us not versed in the differences between milk spotting, water spotting, and the like, do you have a few pictures that might illustrate the point? Thanks again...Mike

[edited to add, I see someone in the thread already asked the question. ]

YaHa

I will say one thing only about dipping coins.


It's not right for the top company to miss a cleaning/altered coin. That's why it's hard to believe that this practice is allowed.

As I have asked many questions before about how to clean coins properly this would be just for my own collection. Not to clean a coin to be slabbed and maybe it is someone else's problem of spotting down the line. It's not right.

As anything else in life there are no gurantees but to clean coins post mint processes and submit again it's not right.

Lastly as I have over 1000 ASE's and many other 1000's of coins fresh from the mint I have nevered experienced a milk spotting effect just natural or metal alloy failure of toning.

I am learning more and more about the game and it seems you have to be on top of the best also or your money can be worth the same amount before you got it nothing.

Jcarney

<< <i>The nature of the spotting is the same in either case, which makes it logically clear that it is related to mint produced surface contaminants.
Russ, NCNE >>



I read somewhere, long, long ago, that the spotting was due to the wash the planchets received before being struck. Some of the coins apparently don't get rinsed thoroughly and the rinse residue is actually struck into the coin.

Jcarney

Wow, freaky. I didn't realize this was an old thread. At least both my replies, over three years apart, were consistent!

adamlaneus

I think there is a general misunderstanding as to what a milk spot looks like.

I once thought they were the white milky blotches so common on ASEs. It turns out, this is from improper cleaning.

I have an ASE that I got from Becoka. It has a darkish spot on it. It looks like a hole has been drilled into the coin. It is a corrosion pit, a dark shiny spot that has eaten into the coin surface and made a visible, yet small depression. Not a surface effect; a deep defect and it appears to slowly chew its way deeper. I am told that _this_ is a milk spot. But it looks nothing like milk for sure. It looks more like someone took a punch to the coin and made a dirty hole.

ricko

"It's not right for the top company to miss a cleaning/altered coin. That's why it's hard to believe that this practice is allowed."

Most dipping, of a non-corrosive nature (i.e. alcohol, acetone) is not considered cleaning and unless improperly rinsed/dried can NEVER be detected. Period. Cheers, RickO

PCcoins

This seems to happen a lot with 58-d franklins from mint sets. I'm sure it happens to other dates/mm.

morgansforever

I purchased this NGC ASE spot free, and stayed that way for years, then out of the blue, milk spots.

I have two other 96's with the same ugly milking, despite being in Intercept Shields.

The acetone, distilled water, pat dry routine seems to work. None of my 20th Ann. sets are milking, after this method.

Could be pure coincidence, at least it gives me piece of mind.

Eagle was a nice, till I was milked.

Scott