Mark on My 1883-O Morgan, what to do ?

if one has to "hide his work" that would be a coin doctor not a professional


Edit: late to the party

 

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This is going to be fun...GAME ON: @physics-fan3.14 posted the following, my humble opinions in color: NOTE: Mr Poe is an authority on coin grading and has written a very good book - The Art and Science of Grading Coins that I highly recommend for beginners.

In widely accepted numismatic parlance, "skin" refers to toning or patina, which are natural reactions of the coin with its environment. The compounds formed are oxides or sulfides of the coin metal. I believe that's basically what I said so I'll basically agree.

Acetone WILL NOT remove these. Acetone WILL NOT affect toning, if it is natural. Actually, acetone WILL lighten some forms of "toning" color on coins. Acetone will only remove organic compounds (Which ADD "color" to coins) Acetone WILL NOT affect metal comounds. I never said it did; but it's good to let others reading this know.


I'm not sure where you got this from. Do you have a reference explaining this? I, and many others I know, have used "skin" to refer to any natural patina on the coin. Actually "Skin" was defined for me by two different top two TPGS finalizers and one top two TPGS owner so your "beef" is with them. I regard their opinions and definitions over yours. However, in my first paragraph I explained we are both probably saying the same thing.

There is absolutely no need to treat the coin with kid gloves. Easy to say when you don't own it. Imagine if the TPGS's treated our coins roughly. Put the entire coin in a glass of acetone, and leave it there. Remove all of the organic compounds from the surface to help in conserving the coin. If the toning, or any other colors were removed then they were not natural toning and shouldn't have been there in the first place. I'll agree and if you don't like the "raw" color of you coin after its "bath" keep your thoughts to yourself as you were warned.

I don't understand why this would be the case. Natural toning on gold is a compound of silver and copper sulfides - and should be unaffected by acetone. If the color changed by application of acetone, then the compounds on the surface were organic in nature, BINGO! News Flash. The elevator is working - and that is EXACTLY how "skin" gets lightened - thank you very much, bow and exit stage right. and shouldn't have been there in the first place. Do you have pictures, or some sort of explanation for this claim? I'm truly sorry I don't but the next time I play with a $20 Saint with "skin" that I OWN, I'll make one for you that you can put in the 2nd Edition of your book.

Water will not chemically affect the surface of the coin (unless there are solvents present) Like those in tap water and sea water (adding salt water here is not playing fair - I'm making some bad humor). If water affects the coin, the substance shouldn't have been there in the first place. There is a big difference between natural oxidation, and reaction between sulfur compounds in the environment, and surface contamination from foreign materials. Well said, I agree.

There is a huge difference between conservation and doctoring. The semantics are beyond the discussion of this post (although other posts have dissected the issue). True conservation seeks to stabilize the coin and remove damaging substances. If a surface is impaired after conservation, it was because the contaminants had damaged the coin already. OR the conservation "Ex-Pert" screwed up or the coin just "blew up." Bad things happen to good coins Doctoring, however, seeks to alter the surface of the coin to improve the apparent appearance of the coin. And conservation ALSO "seeks to alter the surface of a coin in order to improve the apparent (?) appearance of the coin.

Dipping is doctoring. NEWS FLASH for all you "purists" at least 90% of conservation involves some form of chemical treatment (DIPPING). Dipping removes metallic compounds from the surface of the coin. Sometimes, a silver solute is required to remove the compounds (and, a properly performed dip is still considered market accepable). However, dipping is doctoring. Answered above.Acetone does not change the metallic structure of the surface of the coin, and thus is not considered doctoring - it can only remove organic compounds. I'll go with that in theory; but BOTH acetone and other chemical treatments remove something if it is there. Often when this is done the coin lightens.

Without closer examination, I'm not sure what caused the mark. Well, one rookie (me) and one or two other advanced numismatists are: It's called "slag" and it produced a flaw on the coin that acetone should have no effect on. If it is a planchet flaw, then acetone won't remove it (of course). However, treating the entire coin in acetone will cause no adverse effects to the coin (if properly done), and will raise absolutely zero alarms.[/QUOTE] So go for it. If you are lucky, you will just "strip" the coin. If you mess up, you'll just hairline it.

 

Put down the 5-hour energy insider!

 

Well, lets paint a rock chip on a four million dollar Ferrari and not blend it in. Ham-Handed coin collectors have probably ruined more coins than were minted in the US last year. Close your eyes and imagine a dull Morgan with a bright silver dot in the field where a carbon spot was removed and the "skin" was not blended. I'll bet conservation is like making sausage, we like the result but don't wish to see the process. Get real!

 

@Insider , that is a lot of back and forth. I think you are missing the basic point of what I'm saying: acetone will do no damage to the coin, will not affect the metallic compounds, will only remove organic contaminants that shouldn't have been there in the first place, and will be completely undetectable if done properly.

Bear: if done properly, acetone will not damage your coin at all. You can leave it in as long as you like, because it will not affect the actual coin at all - only organic compounds on the surface. In actuality, you really don't need to leave it in the acetone for more than a few minutes, because it will dissolve the contaminants fairly quickly (in all except for the most extreme cases). For far more scientific explanation and information (and an example of a very extreme case), see my thread here: http://boards.collectors-society.com/ubbthreads.php?ubb=showflat&Number=5536102#Post5536102

 

He's right insider. You cross the line to doctoring if you need to do anything more than remove a spot. If you mess up or the metal aged at a different rate and you need to blend it, that crosses the line. Only exception is windowsil toning. If, in a month or two, it tones to a point of totally obscuring and hiding the spot area that's acceptable. I disagree with the rigid definition physics subscribes to but trying to quickly blend out a spot removal that went bad outside of the natural gamble and time of the windowsil method is crossing the line. That includes ovens, potatoes etc

 

Well the banter is there and the information given is a great help. Without question I'm glad I have brought out the best of all in this post. You all are a huge help and I value everyone's input. WOW ! I'm glad I didn't use vinegar on this.

 

So go for it. If you are lucky, you will just "strip" the coin. If you mess up, you'll just hairline it. [/QUOTE]

Please talk a little more about how putting the coin in an acetone bath will cause hairlines.

 

it contains gremlins that eat the organic matter and they are really hungry

 

Oh boy !

 

Please talk a little more about how putting the coin in an acetone bath will cause hairlines. [/QUOTE]

If the coin is not dried properly (It's not the bath). And letting the contaminated acetone dry all be itself on the coin just leaves a film, ah more and different "skin" as some wish to call it.

 

So, if you give a coin an acetone bath, and then "dry" it by rubbing it vigorously with a paper towel, it gets hairlines -- and that's because of the acetone bath?

If you "let contaminated acetone dry on the coin", first, you're doing it wrong -- you use two or three separate baths, as I understand it. Each time, the drop or two of contaminated acetone from the previous stage is diluted by the entire bath full of clean acetone. This is not going to leave a film, at least not one detectable by the human eye (or TPG instruments).

Suppose you've got a Morgan dollar that's caked with gunk, a full gram (and at that point we're talking "wad of chewing gum" amounts). Dip it in 50ml of acetone, about a shot-glass worth. Assume that 100% of that gunk dissolves in the acetone.

Pull the coin out. Let the acetone, with its very low surface tension, drip off. You'll have maybe a tenth of a ml of acetone sticking to the coin's surface, and that bit's share of the gunk amounts to about two milligrams.

Now do another bath. Those two milligrams dissolve into another 50ml of clean acetone. Pull the coin out, let it drip. Again, maybe 1/10ml of acetone doesn't drip off -- but that bit is carrying four micrograms of gunk.

Now, do the third bath. Those four micrograms dissolve into another 50ml of clean acetone. Pull the coin, let it drip, and the acetone staying on it until it evaporates leaves behind eight nanograms of the original gunk.

And a full gram of gunk is a big stretch to begin with.

 

Very nice post. Unfortunately you may wish to brush up on your technique. NEVER, rub a Q-tip over the surface of a coin (unless you are doing the hairline test I mentioned above). It is better to roll it gently over the surface.

And...I've see a large cent greener that the one you conserved done in about 45 seconds from the time it left the flip to when it was dry and ready to be straight graded. Just saying...as I don't have the luxury of a good soak.

 

@-jeffB Says:

So, if you give a coin an acetone bath, and then "dry" it by rubbing it vigorously with a paper towel, it gets hairlines -- and that'sbecause of the acetone bath?

Insider replies: You know better than to twist my post in order to ask as silly a thing as this! Please...

If you "let contaminated acetone dry on the coin", first, you're doing it wrong -- you use two or three separate baths, as I understand it. Each time, the drop or two of contaminated acetone from the previous stage is diluted by the entire bath full of clean acetone. This is not going to leave a film, at least not one detectable by the human eye (or TPG instruments). Well, now you are providing somewhat "proprietary" information to the unwashed masses. Soon we may not need professional conservation services. I should be very interested to know all the other little secrets you wish to share. Perhaps you could write a detailed post for us. I would vote "Best Answer" for it.

Suppose you've got a Morgan dollar that's caked with gunk, a full gram (and at that point we're talking "wad of chewing gum" amounts). Dip it in 50ml of acetone, about a shot-glass worth. Assume that 100% of that gunk dissolves in the acetone.

Pull the coin out. Let the acetone, with its very low surface tension, drip off. You'll have maybe a tenth of a ml of acetone sticking to the coin's surface, and that bit's share of the gunk amounts to about two milligrams.

Now do another bath. Those two milligrams dissolve into another 50ml of clean acetone. Pull the coin out, let it drip. Again, maybe 1/10ml of acetone doesn't drip off -- but that bit is carrying fourmicrograms of gunk.

Now, do the third bath. Those four micrograms dissolve into another 50ml of clean acetone. Pull the coin, let it drip, and the acetone staying on it until it evaporates leaves behind eight nanograms of the original gunk.

And a full gram of gunk is a big stretch to begin with. Thanks but all this was unnecessary. You expressed yourself very well in the second paragraph. What a waste of a good stick of gum!

 

Okay, here's the easiest way to answer this:

If you had a fully sealed environment containing the acetone, you could leave the coin in it "forever" without causing problems. The problem occurs with the acetone evaporating. If it evaporates, any contaminants that dissolved into the acetone would possibly be redeposited onto the coin surface. So, the goal is to get the coin out before more than half of the acetone has evaporated. Once you're ready to transfer the coin from the bath, have a second bath with acetone prepared. As you put the coin into the second bath, give it a swish to have the particulates dissolve into the "new" bath. At this point, I personally do something dumb and I rinse the coin in distilled water before air drying it. This is mainly because I don't want the acetone evaporating on the surface of the coin. Chemistry actually says not to do this, as you're rehydrating the surface, but it's my personal method. After it air dries for 24 hrs, I place the coin into a mylar flip. Again, not actually the right way, but how I do it.

Others may recommend a third acetone bath to remove any remnants of whatever organic material, with a quick dab dry of each side then back into the storage. That's fine too.

Things you want to avoid until you actually have some practice with it:

1) Physical manipulation of things on the surface. This includes using Q-Tips, rose thorns, toothpicks, etc. It also includes rubbing the surface with anything.

2) Spot cleaning.

3) Surface color blending.

Basically, treat the coin how you would a wine stain on your rug. Try to get it out, but not at the expense of destroying the rug or leaving a huge white spot in the middle of cream colored rug.

 

You livin' at Franks house? @Treashunt......I'd be most scared.....same shag rug.

 

Something going on here Frank?

 

I gently' and sometimes slightly vigorously, rub coins with qtips while submerged in acetone if it calls for it and haven't had a details grade from one yet

The key is using it while the coin is submerged to add a touch of lubrication. It's fluffy cotton @Insider. Just about the softest stuff on the planet. That said there's no need to "dig in" with a ton of force as if the qtip ain't working with gentle rubbing it ain't gonna work period. Then you break out the toothpick or cactus spine / fruit tree thorn

 

That black mark is no worse than all the stuff forming around the obverse and reverse rims. If you don't like the black mark put it in a plate full of acetone. A minute or two should do it. If it is still there after that soak, most likely its not coming up. Personally, I would put that coin in my preferential storage as is.

One thing on Q-Tips. I would buy the Q-Tips with the long wooden handles. These Q-Tips are used in the electronic industry. They are more tightly wound and less likely to hold on to gritty substances. A trip to the electronics store may surprise you to the tools for use in numismatics.

One thing I did not see get mentioned in this thread was mirrored like surfaces. I will attest to the fact I have not tried every known substance to man, but, close. I believe there to be no material known to man on this planet or any other galaxy in this universe that is soft enough that will not put hairlines on mirrored proof like surfaces. The phrase do not touch can not be overemphasized.

I go through gallons of acetone. This and other cleaners should have their own thread. Any coins I pull out of circulation that are destined for the accumulation pile go into an acetone bath. One never knows where that coin has been.

 

No, I'm not going to read all of this...but would like to see how it comes out.