Advanced Coin Conservation

What was the predip and dip before they started on their 'special'. The only compound I am familiar with that could have an effect over the commercial dips is a cyanide solution, which should never be done without forewarning as moisture can decompose Sodium cyanide to hydrogen cyanide gas, so I hope you can confirm it wasn't.

 

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All I can say is what was explained to me in very basic steps.

When a coin is suitable for conservation, it's a several step process. Ideally, as much of the contamination/toning/residue is removed before the final step (the dip). Often, a final dip is not needed.

EDIT: I forgot to add that in some cases, even after all the steps and a final dip is done, there still my be detracting stuff on the coin. That was the case with the coin in the OP. After the final dip, another step was added to remove the spots.

As there is a lot of money involved with conservation, the people who offer the service are secretive. Employees can be sued for releasing proprietary info about the techniques and chemicals.

Most dealers/collectors just see something on a coin and stick it into the dip. They think the concentration of the dip is an important consideration. In many cases the "stuff" does not come off completely necessitating another dip. The more you dip a coin the more chance of making it look unnatural.

I've been in several places where coins are cleaned. I remember one "boiler factory" in the mid-west that treated every silver dollar they sold in an ultrasonic cleaner with hot dip! That was in the 1980's. Coin cleaning as done at the various conservation services has gone far beyond that. Nevertheless, ultrasonic cleaners with dip are still used.

 

This is relevant to my interests.

I happen to have an ultrasonic cleaner, and I asked here (soon after I joined) about using it to clean coins. I was warned that it would likely damage my coins, but I wonder if there was an assumption that I would just plop them into the metal basket and start them buzzing.

I still haven't done the experiment where I do that with a few Zincolns, then try it again with a Zincoln in a nylon net, then again with soft-tip tongs.

 

Curious questions: Can they restore coins that have been ruined by improper dipping? Is this focused specifically on proofs, or does it venture further? Does it favor any specific metals? Did they give out any word on the cost of conservation and how to submit coins?

 

This is what I have learned: Ultrasonic cleaners are dangerous...LOL. They must be used properly. The reason they are used for conservation is the chemicals reach deeper into the microscopic surface of the coin. Additionally, for the same reason, chemicals used to neutralize the coins do a better job.

1. Nothing can touch the coin except holding it in tongs. Any type of "basket" (including nylon) that can rub on the coin will eventually affect the surface (rub).
2. Heat helps, but these cleaners are more expensive.
3. Coin must be watched and agitated at all times to prevent the microscopic bubbles from digging a hole into the surface.



Seattlite86, posted: "Can they restore coins that have been ruined by improper dipping?" No, but in cases of "dip burn" it can be lightened.

"Is this focused specifically on proofs, or does it venture further?" It is just conservation of any coin. So far, major stains on SE cannot be removed but I should think someone must be working on it.

"Does it favor any specific metals?" Again, conservation is different for different metals. They do different things with gold than they do with silver, nickel, or copper.

"Did they give out any word on the cost of conservation and how to submit coins?"

No, AFAIK three of the major TPGS charge for conservation. Call each for details. At this time, IGC does not. That's where this demonstration took place.

 

Naval Jelly (not to be confused with nose oil).

 

Navel Jelly???

 

From Navy Bean soup.........

Insider? Glorious thread..........

 

...maybe that was in one of those waivers they make everyone sign but no one actually reads.

 

You don't read it 'cause you're already dead from cyanide poisoning..........

 

"Excuse me, what's this about the cya"

 

Bingo.........

 

Ken, don't drink and dip the same time.

"It all happened on June 24, 1922. World-renowned numismatist J. Sanford Saltus was discovered in his room at London’s Hotel Metropole, lying on the floor, fully dressed. He was dead at age 69, but not from natural causes.

A coroner’s jury labeled Saltus’s passing as “death by misadventure,” according to an account in the August 1922 issue of the American Numismatic Association’s publication, The Numismatist.

The day prior to his death, Saltus purchased a small quantity of potassium cyanide for use in cleaning silver coins he had just purchased. The Numismatist noted, “Potassium cyanide, although one of the most deadly poisons, is frequently used by collectors in cleaning coins…”

Unfortunately, at some point after Saltus retired to his room, on the 24th, he ordered a bottle of ginger ale. “A glass containing the poison and another glass containing ginger ale were found side by side on the dressing table,” The Numismatist reported, “and it is believed that while interested in cleaning the coins he took a drink of the poison in mistake for the ginger ale.” Ouch!

At the time, Saltus, who hailed from the United States, was president of the British Numismatic Society as well as one of the major benefactors of the American Numismatic Society. A prestigious award for medallic art is still presented each year in his honor by the ANS."

http://www.numismaticnews.net/flipside/drinking-and-coin-cleaning-a-deadly-mix

 

Happily Jim, I don't drink and drive, nor do I drink and dip. I've seen that clip before.......poor fellow.

 

"I love the smell of napalm in the morning... It smells like victory."

 

http://www.loctiteproducts.com/tds/S_TRMT_NAVAL_tds.pdf

 

One of the things that occurs to me is that any coins that are candidates for any kind of dipping, acid or base, should be of high grade (XF or better) and should be extremely clean.

 

I am working on a silver proof set now. E-Z-EST Dipped and all spots are gone. Coins look great ---- EXCEPT ---- When I turn the coin sideways I can see a gleam from the dip. I am planning to neutralize it later and then dry to see if the bluish gleam disappears. If it does --- Grading. If it don't ---- Silver Album!!

Either way I learn and have fun with it!!
Rick