"Dipping, not cleaning"

From NGC: "We believe it is OK to reward a dipped (but not over-dipped) white coin, if the dipping was done properly. This is because very few blazing white coins have escaped dipping and because dipping is a common and generally accepted practice in the hobby and business."

From a semi-newbie:

Can anyone elaborate? What gets dipped? What's a white coin? (silver?) And what does it get dipped _into_? And what does it do?

Thanks!

 

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Dipping a coin removes the layer of silver sulfide (toning) from the surface of a silver coin. As a result, a toned coin can be transformed back into a blast white coin that appears much like the coin looked when it was first minted. The problem with dipping is that if the coin is over dipped (too long) or repeatedly dipped, the dip can remove the metal flow lines created during the minting process from the surface of the coin. It is these flow lines that create the luster of a coin. Without them, the dipped white coin will have a flat, lusterless, washed out appearance.

Personally, I rarely ever recommend dipping a coin because I find much pleasure in the originality of toning. However, there are times that a hideously toned coin would benefit from being dipped. Please see the photographs below. Some collectors would find the toning on the first coin so distracting that they would dip the coin to make it look like the second photo.

Before Dip (Toned)
​

After Dip (Blast White)
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Now of course these are not the same exact coin, the first is an MS66 1924-D (photos courtesy of Heritage) and the second is a dipped AU58 1924 but it does illustrate the point.

I have never dipped a coin in my life and will never. Therefore I will let someone else tell you the chemical that is used in the dipping process.

 

I've dipped many a coin. If you are just removing toning and not trying to remove gunk, or hide damage there is nothing wrong with it. In fact I just witnessed an 1893 O quarter in XF but toned pitch black and ugly as sin take a dipping and come out an attractive gun metal grey and now a sellable coin, whereas before it was junk.

 

I personally think the dipping depends on the series. I think NGC and PCG are tougher on Morgans than other series. Maybe because of the abundance of high grade coins.

 

So, I have some ugly-as-sin cheap Roosevelts (stashed in an old Whitman album for 35 years, and just rediscovered this year -- no exaggeration), and unless my memory fails (which is entirely possible), I coulda sworn some of them looked pretty nice when I put them there in the 1970's, but the toned in a very ugly way. I'd like to experiment with a coin or two (I can try to post a pic later) . . . (these are coins where I could probably _upgrade_ at a cost of $2.50).

So, what do I use as the dipping sauce?

 

Do not use any of the homebrew concoctions unless you are a chemist. Do not use anything you might find in the kitchen or garage. Chemical "dips" contain sulfuric acid and sodium thiosulfate solutions in specific concentrations. Best bet for nonchemists is to purchase "jeweluster" ( old name) E-Z-Est ( new name). It isn't only a "time" or "number" of dips, but the combination of both. Over dipping can be hard to control with a full strength commercial dip. Best to dilute some to half or 1/4 strength and dip fast and rinse, look, repeat if absolutely necessary.

You know you are removing surface silver with the chemical, and the shorter the flow lines get, the less the cartwheel and luster. There is ALWAYS an effect on the surface, just make it minimal. When the flow lines get close to the level of the coin, it will have no cartwheel and a flat "dead" surface.

You can also use aluminum electrolysis with sodium bicarbonate ( check google), but same effects.

This is not a recommendation to "dip", just if you are going to do it, this might help.:whistle:

Jim

 

Very good post.

 

Thank you very much for that info

 

How bout that..shoulda said "dipping" at the beginning of my "cleaning" thread. Who knew?

 

Here is a real ugly one, would a dip get rid of the tarnish streak on the reverse? Since it is worn smooth and luster wouldn't be lost, what harm could a dip do?

 

None of the photos thus far would warrant a dip IMO. Pauls SLQ example I'd have to see in my hand, but frankly that blast white isn't all that attractive either. I think the reasoning is poor on the part of the TPGers anyway. Just because dipping was largely practiced prior to the 1940's on nearly all coins, espeically Morgans, is no reason to reward modern dippers, UNLESS, the coin really needs some intervention because the eye appeal is just so darn bad. If I was practiced at it, I have one single Merc in plastic that I'd dip if I could because the toning makes the coin almost look scratched. Black toning is really bad. But the coins that I really think need conservation are the Big Coppers, especially the US coppers before 1800. To me, this is a curator issue. Precious artifacts need maintenance in addition to proper storage.

If this doesn't seem to jive with my DON'T CLEAN YOUR COINS rants, then oh well. Your not understanding the context of the discussions.

BTW Jim - Baking Soda and Al Electrodes? Great thing to teach the kids.

Also - FWIW - Pure Acetone is the dipping agent of choice among most conservationists.

Ruben

 

Ruben, acetone would not considered a "dip" type of chemical for the process that NCG, PCGS mention. The "Dip" they refer to is a chemical reactive to metal, which acetone under normal conditions is not.

Ruben, the process uses Baking soda, aluminum foil, table salt, and water at 60 deg. Centigrade. No electrical connection needed. How are the "kids" going to be affected?

Jim

 

Dipping should NEVER be done on circulated coins

 

I agree with AJ - this coin does not warrant dipping and would probably turn out looking worse. This coin looks nice just the way it is.

 

I can't beleve you're still on this lol..

I wouldn't dip a coin that is this worn... I don't believe a blast white worn half dollar would look to appealing. To keep the toning would be your best bet.

 

how about these?

These (and a few like them) are what prompted the question that started the thread. As you can see, I think, these are AU/UNC-ish, but mightily discolored (sitting in old Whitman albums 30 years) . . . I really think they were fairly good looking when I put them in the albums.

So, nu? worth a try at a dip?

 

Man o Man, 1853 was a great year...one of my favorites of all time! There's an 1853 Half Dollar on eBay right now that was dipped. It probably was a decent coin before whoever did it. I don't know if it's right to drop an eBay number in here, so I won't do it. You can find it very easy though, just look for the blast white 1853 circulated Half Dollar that looks like they had a hard time even taking a picture of it. I like this coin much better than that one! It's a shame what happens to special coins like that when people try dipping, imo.

 

I think you would be surprised at how bad a worn coin can look after cleaning/dipping/etc. Cleaning seems to accentuate the flatness of a worn coin.

 

Those are georgous and highly desirable coins, dipping would ruin them. Old genuine album toning is the desired effect, coin doctors have tried to duplicate that look forever, don;t mess with them at all. They look sweet !