Coin cleaning question.

I know that cleaning a coin, aside from soap and water, is a big no-no. Why is this a no-no? Why does it detract from the value of a coin? I know that many people prefer an original, uncleaned coin that might be a little dirty than the same coin that has been cleaned. Is there a specific reason why a cleaned coin is worth much less than the same uncleaned coin (maybe in a lower codition) Or is this just one of those long established rules that is just there? Thanks.

 

Log in or Sign up to hide this ad.

What makes you think that soap and water is OK? The soap leaves chemical residue, and when people wash things with soap and water they generally rub them either in the cleaning, or in the drying. I've seen some disastrous results from "just a little soap and water".

The "why" of the general disdain for cleaning is very simple - every method that removes dirt either removes, marks, or otherwise alters the metal.

Rather than rehashing the dozens of postings which have gone into detail on this subject, I'll just remind you of the "Search" button at the top of the page. Use it to find the many, many threads which have discussed this issue in detail over the past months.

 

My personal opinion is that cleaning is wear, and should affect the value of the coin in the same way as equivalent wear. But cleaning is treated as a special type of unforgivable wear, and there is no way to change that at the present time. So absolutely NEVER clean any coin in any way with anything at all no matter how harmless it seems unless you are happy with a much less valuable coin than you started with.

On the other hand, I've also felt there might be some merit to buying already cleaned coins if they can be obtained at significant discounts from uncleaned coins of the same date, mintmark and wear. It might enable you to obtain some coins normally out of reach, and the coins COULD [but the odds are against it] appreciate in value if attitudes toward cleaning change in the distant future. The downside would be that you end up owning coins that would be somewhat difficult to resell.

 

Another reason why it can be bad to clean a coin is that you disrupt the surface layer of the coin exposing more reactive metal to the elements and increase the likelihood of future corrosion.

When a fresh coin is made its surface is very reactive and the metal seeks to combine with chemicals in the atmosphere in order to become more stable and less reactive. A layer forms on the surface of the coin that is less reactive than the fresh coin. When you clean a coin you disrupt this layer and make the coins surface more reactive until a new layer forms. Depending on what the coin is exposed to the coin can corrode or discolor easier.

An exception to this general rule is if there is aggressive corrosion taking place on the surface of the coin. For example, if the coin was exposed to PVC and the PVCs plasticizer reacts with the coin and makes that green looking stuff which is actually a form of hydrochloric acid which can eat into the coin if not removed. Then careful removal with an appropriate solvent can actually be a benefit the coin.

 

OK. Fair enough. How often are circulated coins coated with oils and salts from human hands?

One would think that removing human oils, grime, and salts from a coin, then placing the coin in a sterile envelope, would be preferable to allowing the grease, grime, and salt of ages continue to work on the metal. Million-dollar firearms are cleaned with solvents and lightly oiled. Priceless ancient museum artifacts are cleaned! Dinosaur bones are cleaned. Oil paintings are restored and cleaned. You guys are a tough group. :smile

 

If an incirculated coin or proof is going to be placed into a holder or an album and it was accidently exposed to oils or sweat, it might be a good idea to carefully degrease the coin in an appropriate solvent, such as pure acetone, before placing the coin in the holder or album. But only if you know what you are doing because it is easy to contaminate the coins surface if the solvent isn't pure and it is easy to accidently make hairline scratches on the coin.

For circulated coins, it is usually better to not remove anything off of the surface of the coin unless the coin is being attacked by an active corrosive agent. If you remove the surface "crud" all wear marks and/or scratches are typically magnified in appearance and oftentimes the coin ends up looking dull and lifeless. In other words, the eye appeal of the coin typically becomes negatively impacted by the cleaning. The unnatural gray appearance (or pinkish orange for copper coins) coupled with the greater noticability of every scratch and mark on the coin is a big turn off to a collector who is putting together a matched set of original looking coins. In an album the cleaned coin sticks out like a sore thumb.

 

Well we all get the point that we never WANT to clean a coin. This is posted over and over and over any time some asks about cleaning. But I never been able to determine exactly how to clean a coin that needs or must be cleaned! Everyone is quick to point out how not to clean but not quick to answer how to.
I know acatone for PVC – what about corrosion on nickel or nickel clad coinage? Are all green spots and specks PVC and/or corrosion?
If the coin has PVC or corrosion on it isn’t it basically worthless and cleaned properly only increase its value?

 

I think there is a confusion that is going on right now.

While MOST cleaning will ruin the values, you have to understand that it is the degree of the cleaning that will ultimately determine the prices of the coins.

Depending on how you clean the coins, most of the time, even using micro fibre cloth will make scratches. I mean, have you used that to wipe your skin? How does it feel? Does it hurt? If it does, a coin will get some sort of "damage"! Any materials harder than that will obviously hurt!

Usually a collector shouldn't try to clean any coins unless the following:

PVC damaged coins
Rusted coins (but make sure you know what you are doing!)
Verdiges
Perhaps ancient coins that were dugged out *but that requires a different method of cleaning*

If actions are not taken on these types on coins, most likely these actions will continue on until the coins are "eaten" up, which usually proper actions are recommanded for only such damaged coins.

There are no other reasons why you should clean other coins. Maybe you can clean coins and tada, it's worth slightly more but really - if coins were worth more if cleaned, everyone would be doing it but no one is. Furthermore, you are doing a bad thing for the enviroment for dumping such "waste" and useless usage of water and solvents.

Where is the fun of seeing several hundred years of sweat and oil on coins that faced plenty of "transactions" and that got cleaned within a few mins?

 

What does Biox do to the coin? Will it just leave a discolored spot where the corrosion was?
Thanks

 

To me, PVC is poly-vinyl-chloride, and Au is the atomic symbol for gold.

What is PVC to you folks? It can't be the plastic, right?

 

That is right!

Speedy

 

Yes, PVC or the cheap plastic. PVC normally wouldn't do much damage under "usual" circumstances but when it breaks down, it releases chlorine, which is a complete no-no.

 

Never fear, ma'am, for I am an expert! ... ooops!!

Like the Sistine Chapel and the Mona Lisa, coins are cleaned by experts. Do you think that someone who buys a Picasso washes it it "just soap and water" to get "a little bit of the dirt off"?

Coin collectors are famous for being so cocksure of themselves that they ruin their artifacts ... and all they can worry about having done that is the loss of resale value. These are pieces of history. Be careful with them.

Have you taken the ANA Class in Conservation?

"... a man will fight, he'll fight, he'll fight
to prove that what he does not know is so!"
Yule Brynner as Mongkut (Rama IV) of Siam
singing "It's a Puzzlemen" in
Rogers and Hart's The King and I.

 

When I think about it, cleaning a coin is "editing" it and makes it seem ungenuine as someone has tampered with it. This includes soap and water, because you are trying to change the coin. In addition, cleaning a coin is quite noticable: I asked for 11 Sackies at my bank and got them. About four or five of them gave off a filthy rainbow-y look, so I assumed (after speniding them - I do my part to circulate Sackies...) they had been cleaned.

 

When a TPG grades a coin should it matter who did the cleaning? From what I am reading a cleaned coin is a cleaned coin if damaged from the cleaning is a different story! But if TPG's are going to body bag cleaned coins it really should not matter who cleaned it!

 

Cleaning vs Conservation...

I recommend everyone go to the NCS site and read The Conservation of Coins - A Buyer's Guide, here is the link...

http://www.ncscoin.com/conservation/buyersguide.asp​

This will give everyone an idea of what the EXPERTS in the field believe.

Improper cleaning of a coin is a "no-no" and always will be BUT the proper removal of unwanted elements from a coin, to enhance the beauty of the coin, is not.

 

This is a good point. If a coin is "conserved" [cleaned] by experts at one of the TPGs paid to perform this service, and if the coin is subsequently removed from the slab, is it then considered "cleaned" and therefore damaged in the eyes of subsequent collectors?