Dipping coins questions

Aspie_Rocco

It is my understanding that dipping a coin removes a thin layer. Is this correct? If so, would dipping a coin remove evidence of a previous cleaning that was deemed unacceptable to the market? This is my
most important question. Now a few more...

If dipping a coin does remove a layer, how is this market acceptable?

Why is dipping not considered a surface alteration?

Does dipping a coin erase an improper cleaning?

What is the difference between a dip and an acetone bath?

PerryHall

Dipping a coin will not remove the hairline scratches resulting from an improper cleaning.

Rondor

Dipping a coin removes luster. I would never ever dip a coin.

If I had something potentially of great value, I would send it to PCGS for resto.

jmlanzaf

@Aspie_Rocco said:
It is my understanding that dipping a coin removes a thin layer. Is this correct? If so, would dipping a coin remove evidence of a previous cleaning that was deemed unacceptable to the market? This is my
most important question. Now a few more...

If dipping a coin does remove a layer, how is this market acceptable?

Why is dipping not considered a surface alteration?

Does dipping a coin erase an improper cleaning?

What is the difference between a dip and an acetone bath?

We're talking atomically thin. Rub your hands against each other. Do you see the pile of skin cells that sloughed off? No. Well the skin cells are 1000x thicker than the surface layer removed by a light dip.

If it was improperly dipped, you will see loss of luster. No amount of further dipping will restore the luster. It's the equivalent of side swiping a guard rail with your car and then deciding to do it again to remove the evidence of the 1st swipe.

jmlanzaf

Dipping a coin is only market acceptable when it leaves no evidence of the dipping. It is considered a surface alteration... if there is visible evidence of the dip.

Acetone removes surface dirt not metal. Dip removes an atomically thin layer of metal.

Aspie_Rocco

@jmlanzaf said:
Dipping a coin is only market advertising when it leaves no evidence of the dipping. It is considered a surface alteration... if there is visible evidence of the dip.

Acetone removes surface dirt not metal. Dip removes an atomically thin layer of metal.

So then would a dip that removes a thin layer also remove the shine of a gently cleaned coin?
I do not have an example to share, however, I have seen coins (ms graded) that seemed like they were not over dipped but had a slight look of a dip after a cleaning.
I am still trying to learn how to spot subtly cleaned coins. I cringe buying anything raw after so many have been deemed “cleaned” by our host or other experts.

Che_Grapes

Acetone dip is not considered cleaned. Mostly hairlines are caused by abrasion- even a Qtip can cause hairlines. If you dip in acetone then don’t rub it dry. I’ve successful dipped coins in acetone to remove pvc and other stuff and got a straight grade.
This one is an example: it had lots of pvc and debris that I dipped to remove (most of it) and it was straight graded:

MFeld

@Aspie_Rocco said:

@jmlanzaf said:
Dipping a coin is only market advertising when it leaves no evidence of the dipping. It is considered a surface alteration... if there is visible evidence of the dip.

Acetone removes surface dirt not metal. Dip removes an atomically thin layer of metal.

So then would a dip that removes a thin layer also remove the shine of a gently cleaned coin?
I do not have an example to share, however, I have seen coins (ms graded) that seemed like they were not over dipped but had a slight look of a dip after a cleaning.
I am still trying to learn how to spot subtly cleaned coins. I cringe buying anything raw after so many have been deemed “cleaned” by our host or other experts.

If a coin has been cleaned, dipping it will not make it appear uncleaned.

tommy44

@Rondor said:
Dipping a coin removes luster. I would never ever dip a coin.

If I had something potentially of great value, I would send it to PCGS for resto.

.....and they will most likely "dip it" if removing anything other than organic material.

I (foolishly) dipped several Morgan dollars in the late 1960s and 1970s to remove tarnish (now referred to as toning) and they were subsequently graded MS64 and MS65, some proof like, by TPGs and awarded CAC stickers. If done properly dipping can sometimes be a good thing.

ricko

@Aspie_Rocco ... Acetone only removes organic material. No effect on metals. You may not like what you see when the organics are removed, since they could be hiding defects, tooling, hairlines. Cheers, RickO

lermish

What does PCGS do to restore coins? Their FAQ is very light on the details. Are they just acetone bath and/or dipping on our behalf and offering a grade guarantee if something goes wrong?

Rondor

@tommy44 said:

@Rondor said:
Dipping a coin removes luster. I would never ever dip a coin.

If I had something potentially of great value, I would send it to PCGS for resto.

.....and they will most likely "dip it" if removing anything other than organic material.

I (foolishly) dipped several Morgan dollars in the late 1960s and 1970s to remove tarnish (now referred to as toning) and they were subsequently graded MS64 and MS65, some proof like, by TPGs and awarded CAC stickers. If done properly dipping can sometimes be a good thing.

I would never trust myself to do that with a good coin.

Paradisefound

What kind of solution mostly used for dipping?

jmlanzaf

@Aspie_Rocco said:

@jmlanzaf said:
Dipping a coin is only market advertising when it leaves no evidence of the dipping. It is considered a surface alteration... if there is visible evidence of the dip.

Acetone removes surface dirt not metal. Dip removes an atomically thin layer of metal.

So then would a dip that removes a thin layer also remove the shine of a gently cleaned coin?
I do not have an example to share, however, I have seen coins (ms graded) that seemed like they were not over dipped but had a slight look of a dip after a cleaning.
I am still trying to learn how to spot subtly cleaned coins. I cringe buying anything raw after so many have been deemed “cleaned” by our host or other experts.

You could harshly dip a coin and roughen up the surface so it's not shiny, but that really won't be an improvement.

jmlanzaf

@lermish said:
What does PCGS do to restore coins? Their FAQ is very light on the details. Are they just acetone bath and/or dipping on our behalf and offering a grade guarantee if something goes wrong?

There's other things they could do, laser ablation for example. What they do, I don't know.

PerryHall

@lermish said:
What does PCGS do to restore coins? Their FAQ is very light on the details. Are they just acetone bath and/or dipping on our behalf and offering a grade guarantee if something goes wrong?

I'm sure their techniques and the chemicals they use are proprietary (trade secrets).

jmlanzaf

@Rondor said:

@tommy44 said:

@Rondor said:
Dipping a coin removes luster. I would never ever dip a coin.

If I had something potentially of great value, I would send it to PCGS for resto.

.....and they will most likely "dip it" if removing anything other than organic material.

I (foolishly) dipped several Morgan dollars in the late 1960s and 1970s to remove tarnish (now referred to as toning) and they were subsequently graded MS64 and MS65, some proof like, by TPGs and awarded CAC stickers. If done properly dipping can sometimes be a good thing.

I would never trust myself to do that with a good coin.

You practice on the culls.

MasonG

@jmlanzaf said:
You practice on the culls.

It certainly wouldn't hurt if those with questions about how dipping affects coins went down to their local coin shop, bought a jar of ezest and a handful of toned coins out of the dealers melt bucket and did some experiments themselves.

amwldcoin

@PerryHall said:

@lermish said:
What does PCGS do to restore coins? Their FAQ is very light on the details. Are they just acetone bath and/or dipping on our behalf and offering a grade guarantee if something goes wrong?

I'm sure their techniques and the chemicals they use are proprietary (trade secrets).

Exactly!

lilolme

@Aspie_Rocco

Dipping seems to get multiple definitions. Dipping most often refers to dipping or applying an acidic (acid) solution to the coin that will etch (or eat away) at the surface metal of the coin. eZest is one such solution. The solution is fairly mild and only etches away small amounts of the surface metal if done for only seconds. You will not be able to tell the difference in an un-dipped coin and one dipped for seconds. The level we are talking about is down to the flow lines on the coin and smaller. As you continue to dip the coin, either all at once or over repeated dips over time, then more of the surface metal is removed. Then it starts to affect the flow lines of the surface and you start to see impacts on the luster. Here is a coin I over dipped to see the impact that to much dipping can cause.

https://forums.collectors.com/discussion/1077119/1-1883-o-over-dip#latest

silverbul

sounds like a good project to take two similar coins, dip one in acetone, the other in cleaner that you have to rinse after you dip, ms70 or jewelers cleaner, let them soak say for an hour or a day. i guarantee the acetone will not hurt the coin, the other, not so sure. disclaimer, do this at your own risk. lol. i would do it but i have neither acetone or ms70 at this time and yes i have used both. i stand by my opinion.

silverbul

This is an article from coinweek, just a part.
I. What is dipping?

The ‘term’ dipping has a particular meaning in the field of coin collecting and should not be taken too literally. If a coin is immersed in acetone or ammonia, it is not being ‘dipped’ in the sense that the term is employed in the field of coin collecting. The removal of just dirt, scuff, or substances that are loosely resting on a coin’s surface, while somewhat controversial, is usually not ‘dipping,’ even if a coin is physically dipped.

The definition of dipping is the immersion of a coin in a solution that contains acid for the purpose of stripping toning and metal from a coin’s surface so that the coin is brighter, whiter (for silver or nickel) and/or plainer afterward. A silver coin that is dipped will often become bright white.
SAY WHAT? i agree.

lilolme

@silverbul said:
sounds like a good project to take two similar coins, dip one in acetone, the other in cleaner that you have to rinse after you dip, ms70 or jewelers cleaner, let them soak say for an hour or a day. i guarantee the acetone will not hurt the coin, the other, not so sure. disclaimer, do this at your own risk. lol. i would do it but i have neither acetone or ms70 at this time and yes i have used both. i stand by my opinion.

Agree on the acetone. As far as the others it kind of depends. Here is a recent thread about a large cent and olive oil. In it is a discussion about the acidity of the olive oil versus mineral oil without that. So even olive oil on copper can have an impact.

https://forums.collectors.com/discussion/1077674/draped-bust-large-cent-in-olive-oil-for-a-period-of-months

I did soak a coin in liquid hand soap when I did the over-dip test. There was no impact and still have it with the other 83 O's and it looks just like the un-dipped one. However, I have noticed that dish soaps can cut into toning sometimes. So looking at the active ingredients I notice an acid of some type. Probably there to cut the grease or something. Fairly mild I am sure. Have never tested MS70. No direct acid listed but some stuff I don't know what it is and have not looked up. There is even a citric acid listed for goo gone.

I kind of always wonder about putting a 90% silver coin in eZest and see how long before it is gone. Dime might be best - smallest. Hey could even have a thread contest to guess how long it would take.

slider23

@Paradisefound said:
What kind of solution mostly used for dipping?

eZest is a common dip solution. It contains sulfuric acid and thiourea.

LanceNewmanOCC

one time i left a peace dollar in ezest overnight, knowing it would be flat as a pancake (no luster etc left) by the next day, or worse. it was a vam discovery and whatever was on the surfaces absolutely had to be removed and it was onery. it was already a non-gradable coin and the surface contaminants were prohibiting proper attribution so anyone thinking to leave a coin in power solutions overnight, don't do it except for the exceptions as you cannot come back from this decision.

acetone has proven ok, especially pure.

when dipping proofs, high-dollar business strike etc in ezest or similar, i would recommend to anyone but the professional to have a diluted version or 2.

1 - 100%
1 - 75%
1 - 50%
1 - 25%

something like that.

a mint-state ms66, 67 etc say a morgan can have the luster bomb/halo effect muted each dip if solution is 100% or if it sits too long and isn't rinsed properly.

some people prefer to acetone after a dip as it will remove surface contaminants better than water but some instances water is better for a final rinse, some instances acetone is probably best since it evaporates fast and thoroughly.

fwiw, i counted and there are approximately 1,948,482 threads on dipping coins, just on this forum.

silverbul

https://co"Are You Not Entertained? Are You Not Entertained? Is This Not Why You Are Here?"inweek.com/

winesteven

As @jmlanzaf and others have said, there’s a big difference between quick gentle dipping and harsher dipping.

I don’t buy raw coins, so I don’t dip. However, I’m part of a sizable minority of collectors who prefer the eye appeal of highly lustrous untoned coins, so I recognize that most of the slabbed coins I buy, particularly early 20th Century silver coins, have probably been dipped. However, the dipping apparently was done gently enough, since every one of my coins eligible for a CAC has a CAC.

Here’s one of my coins:

Steve

conrad99

@winesteven said:

Here’s one of my coins:

>

That's a spectacular coin, obviously, and I credit you for recognizing that most (nearly all!) old silver coins have been dipped or otherwise cleaned over the years. A 120-yr-old silver coin would otherwise exhibit 'terminal toning' unless it had been stored in a vacuum the whole time.

The topic gets interesting when you consider how many millions of these coins are 'straight graded' by the TPGs. Obviously a judgment call w.r.t. harsh cleaning vs not.

Separately: I expect this has been discussed, but isn't it high time that the TPGs left some space for CAC stickers?

winesteven

@conrad99 said:

@winesteven said:

Here’s one of my coins:

>

That's a spectacular coin, obviously, and I credit you for recognizing that most (nearly all!) old silver coins have been dipped or otherwise cleaned over the years. A 120-yr-old silver coin would otherwise exhibit 'terminal toning' unless it had been stored in a vacuum the whole time.

The topic gets interesting when you consider how many millions of these coins are 'straight graded' by the TPGs. Obviously a judgment call w.r.t. harsh cleaning vs not.

Separately: I expect this has been discussed, but isn't it high time that the TPGs left some space for CAC stickers?

Thank you for your kind words.

You think the spacing left on the slab for a CAC sticker is tight? I’m very close to completing a very special Indian Head Cent set where every coin in the set has BOTH a CAC sticker AND an Eagle Eye Photo Seal! (Yes, there’s a lot of redundancy having both stickers, but CAC and Rick Snow each weigh various factors differently. As such, I believe this gives me the best of both worlds.)

Steve

conrad99

Sorry, had to walk the dog!

To answer your question: It depends on how much nomenclature the TPG has seen fit to include on the tag. So one size does not fit all! Often they fit just fine, as you know.

Worst when the bean covers a critical bit of information. I'm sure you've seen sometimes it's affixed below the tag entirely—to avoid this issue. But that's not terribly attractive either.

I'm just sort of saying that it would be nice if it were accommodated better. OTOH, we wouldn't want the label to look weird in the absence of a bean. And of course now there are PQ stickers too.

More on topic: can anything be done with an overpolished coin? I have a couple that need etching, or something. Yeah, I know this talk is anathema to orthodox numismatists. But then so is much of this thread.

stockdude_

"Separately: I expect this has been discussed, but isn't it high time that the TPGs left some space for CAC stickers?" Actually if installed vertically there is room. I get your point though

conrad99

@winesteven said:

Thank you for your kind words.

Wow, I now availed myself of access to your online registry and I have many more kind words! Though I see I'm a bit late to that party. You have several coins I'd happily sell my soul for, but having tried that before I can report that no one's buying.

Coins like this one make me weak in the knees.

Expert Comments

Ron Guth

The mintage of Proof 1885 Half Dollars was slightly larger than in the previous year, but it was still a mere 930 coins. With only 5,200 circulation strikes to complement the Proofs, this is a tough date for any collector to acquire. The number of surviving Proof 1885 Half Dollars is slightly above the 1884's and 1886's, but less than the 1882's and 1883's. This doesn't translate to much, since they are all priced roughly the same in average grades. In top grades, this date is slightly tougher than some of its contemporaries but there are a sufficient number of PR66's to go around. Approximately one in five examples are Cameo Proofs. Deep Cameo Proofs are extremely rare (a familiar refrain for Proof Half Dollars of this period).

SlickCoins

So let me get this straight:

Let's say I'm the average collector and by what you all are saying is this:

Oxygen hurts our coins therefore the super microscopic containments of our world 🌎🌍 for surely does also,, hmmm 🤔🧐 does that mean what I can't see is on my coin eating away my color?

Instead of thinking all that lol conspiracy tin hat stuff just slap that in plastic oh we got this

Better yet go to the hobby lobby and buy the slips,, then slide your coin and all that unseen junk across it and then store it,,, you're golden.

In my opinion down the road you'll be saying it was Red when I put it in there and I sealed it,,, what gives?

Well in my opinion you sealed it all right,, increasing the decay rate effectively with the unseen.

PS,,, But it's ok when they do it

winesteven

@conrad99 , you’re so kind. Thanks for your appreciation.

I got lucky in that I bought that PR65+DCAM five years ago from Legend when prices were a lot lower than today. The total PCGS pop for that date in DCAM in all grades is just three, with two in my grade PR65+ being DCAM, and only one DCAM graded higher. But higher graded ones by PCGS and NGC do not merit a CAC, unlike mine and one other graded slightly lower than 66 as DCAM’s that have CAC’s.

Steve

TwoSides2aCoin

If at first you can't flip, you must re-dip

Similar to : " if the grade doesn't fit..."

Cougar1978

I dip raw coins that need it. One recently sold within a day or 2 after being dipped. Did real well on it. Slabs too sometimes.

Paradisefound

IMHO only pro would able to determine if a very slight dipping has occurred

lilolme

@Paradisefound said:
IMHO only pro would able to determine if a very slight dipping has occurred

A coin can be dipped 'very slight' or flash dipped or whatever term one wants to use to indicate a quick dip and the coin will not be able to be identified as such by anyone. Perhaps if someone had microscopic photos of the coin before dipping and then took the same photos after they could detect some changes but not visually. As the dip time is increased, then it starts to become a maybe it has, until finally those as you say 'pro' will say it has been dipped. It still could be market acceptable though.

Paradisefound

Concur

@lilolme said:

@Paradisefound said:
IMHO only pro would able to determine if a very slight dipping has occurred

A coin can be dipped 'very slight' or flash dipped or whatever term one wants to use to indicate a quick dip and the coin will not be able to be identified as such by anyone. Perhaps if someone had microscopic photos of the coin before dipping and then took the same photos after they could detect some changes but not visually. As the dip time is increased, then it starts to become a maybe it has, until finally those as you say 'pro' will say it has been dipped. It still could be market acceptable though.

Dallife

@Che_Grapes said:
Acetone dip is not considered cleaned. Mostly hairlines are caused by abrasion- even a Qtip can cause hairlines. If you dip in acetone then don’t rub it dry. I’ve successful dipped coins in acetone to remove pvc and other stuff and got a straight grade.
This one is an example: it had lots of pvc and debris that I dipped to remove (most of it) and it was straight graded:

How do you dip a coin in acetone and make sure it doesn't develop the white film (or whatever it's called) on it after it dries?

Mr_Spud

@dallife said “How do you dip a coin in acetone and make sure it doesn't develop the white film (or whatever it's called) on it after it dries?”

One way is to put some of the acetone you want to use on a mirror and let it evaporate. If it doesn’t leave visible residue on the mirror then it shouldn’t leave a visible residue on a coin

basetsb

I acetone dipped a few coins. Makes them a lot more presentable. Here are the results.

krueger

@lermish said:
What does PCGS do to restore coins? Their FAQ is very light on the details. Are they just acetone bath and/or dipping on our behalf and offering a grade guarantee if something goes wrong?

I'm sure their techniques and the chemicals they use are proprietary (trade secrets).

I once visted an NGC dealer / PHD chemist who invented MS70 coin cleaner.
In his industrial
Cleaning business wherehouse there on the floor were many GALLONS of the MS70. Not for His industrial business
He would not tell me where they were headed.
But I presumed they were headed to NGC. As
It was invented to clean coins. Go figure. I would guess this is a component of restoration services.
My true experience.