Newbie Question - What exactly is meant by cleaning a coin? 0

[Seamus8]

I am confused as to what constitutes cleaning a coin. I read that cleaning a coin lowers its value. Why is that?

But what is really confusing to me is what is meant by cleaning. For example, is wiping a coin with a paper towel or a soft cloth without any cleaning solution considered cleaning?

For silver coins, is cleaning with silver polish bad?

Can someone please explain how much or little cleaning is acceptable, if there is such a thing?

[Mr.Bill347]

Great question and one we get often. The reason is that any wiping can cause scratches on the coin. These scratches are permanent and cannot be removed . Different solutions can cause the alloys to react differently than normal oxidation. Quite often with a cleaned coin, most of us are unable to even see the damage. Polishing is strictly unwelcome. Yes it makes the coin shiny, but shiny is not always good.  Below are examples of a similar coin on EBay, both NGC graded 1887 Morgan dollars. The first example an MS63 is selling for $95 on eBay. The 2nd example of a similar coin that has been improperly cleaned and graded also by NGC selling for $65. The difference represents a 32% loss due to cleaning. If you have a coin with great characteristics it would be advisable to have it graded rather than attempt any cleaning method. Welcome to the forum and we don’t mind answering questions from folks trying to learn.

[JKK]

1) Because people will pay less money for it, and if valuable, would not straight grade at a TPG.

2) My definition would be: Cleaning is any chemical or abrasive process used to remove some matter that was not part of the coin when minted. Tarnish, PVC slime, gunk, bronze disease, chewing gum, nail polish, etc.--except where the matter is causing ongoing damage to the original coin. When it's putting a stop to deterioration in that way, we consider that conservation. So yes, those methods you described are cleaning.

3) It is beyond bad. Never ask me what I would do to people who do that if it were in my power. They would never do it again.

4) For you, none. Here's the truth with the bark on: The fact that you have to even ask these questions is proof that you, personally, absolutely should not alter the surface of any of your coins until you learn a lot more about the process. That is not a putdown of you, please understand, just an assessment of where your knowledge stands and how you can best avoid harming your coins. In fact, if anything, I respect that you came out and asked the question before doing it. So no sting intended, but that's the plain facts.

You may reach a day when you can somewhat safely indulge in some forms of cleaning, but that day is far away. The people who can do this know who they are and they never have to ask beginner questions. To use an analogy, this is like a first-quarter accounting student sending a résumé to a Big Howevermanyitisnow firm and asking how to become a partner. It's okay to ask, but the guidance you'll get will tell you not to skip all the steps in between.

Here's the main reason for you to look at this differently: When new collectors look at a coin with dark toning, or that isn't shiny, most of the time they think it would be nicer if it were shinier. No, no, no, no, no, no, no. There are uncirculated coins that are so patinated you have to take a good look to realize they still aren't circulated. Most collectors still like them. By contrast, most forms of cleaning create unnatural colors that are twenty times uglier than whatever patina they removed: blast white heavily circulated silver, salmon-pink bronze, and so on. We can tell. Oh, and if you think that your cloth wiping can't possibly be detected, try this. Get a brand new penny. Rub it for about five seconds with a q-tip. Look at it under magnification. Check out all those cute little scratches! Damage, freshly inflicted.

In case any of that seemed to offer a path to encouraging you to clean any coins, or was interpreted that way, let's correct that. Please do not clean any of them. This is the best kindness I can offer you.

[Coinbuf]

Cleaning can take many forms, from a simple wipe with a cloth to use of abrasive compounds and cleaners to chemical "dips".   All of these can have different effects on coins with different types of manufacture and metal composition.   It is difficult for many to think that something that is as hard as a metal coin could be damaged so easily, yet that is exactly what can and does happen, even from something as simple as wiping with a soft cloth.

When a coin for circulation is struck the process imparts flow lines into the surface of the coin, this is what gives a coin its luster and radiance, what we refer to as the cartwheel effect.   When a coin is cleaned those lines are disturbed and the luster is impaired, depending on how invasive the cleaning method will determine how much the coin surface and flow lines are damaged.   But once done that damage can never be undone, there is no way to effectively repair the surface of a coin.   Many have tried over the years and many ways to hide the damage have evolved with varying levels of success.

[EagleRJO]

Just to add to Bill's explanation on the basics related to cleaning coins, simply wiping a coin or rubbing it with your finger can remove mint luster that can't be restored, and add just a few grains of dirt and that will also scratch a coin.

Btw, welcome to the forum.

Edited December 16, 2022 by EagleRJO

[Sandon]

   The term "cleaning" is confusing because the removal of surface dirt or other foreign matter from a coin without abrasively or chemically altering the surface of the coin--cleaning in a literal sense-- isn't considered improper "cleaning" but is instead referred to as "conservation". However, both of the examples you have given would be considered improper "cleaning" and would devalue the coin. Wiping a coin, even with something soft, leaves fine scratches on the coin known as "hairlines" that are undesirable. It constitutes abrasive "cleaning" if the hairlines are sufficiently extensive or noticeable. (If a coin is wet, pat--don't rub--it dry.)  Metal polish chemically alters the surface of the coin, leaving a very unnatural appearance, and the application of the polish is abrasive as well.  Collectors want original surfaces, not surfaces that are damaged or chemically contrived. 

   For a fuller explanation and a number of examples of "cleaned" coins see my custom registry set "Characteristics of Cleaned Coins" at Characteristics of "Cleaned" Coins - Custom Set (collectors-society.com) (right click link for menu to open).

[Seamus8]

On 12/16/2022 at 10:40 AM, Sandon said:

   The term "cleaning" is confusing because the removal of surface dirt or other foreign matter from a coin without abrasively or chemically altering the surface of the coin--cleaning in a literal sense-- isn't considered improper "cleaning" but is instead referred to as "conservation". However, both of the examples you have given would be considered improper "cleaning" and would devalue the coin. Wiping a coin, even with something soft, leaves fine scratches on the coin known as "hairlines" that are undesirable. It constitutes abrasive "cleaning" if the hairlines are sufficiently extensive or noticeable. (If a coin is wet, pat--don't rub--it dry.)  Metal polish chemically alters the surface of the coin, leaving a very unnatural appearance, and the application of the polish is abrasive as well.  Collectors want original surfaces, not surfaces that are damaged or chemically contrived. 

   For a fuller explanation and a number of examples of "cleaned" coins see my custom registry set "Characteristics of Cleaned Coins" at Characteristics of "Cleaned" Coins - Custom Set (collectors-society.com) (right click link for menu to open).

The "Characteristics of Cleaned Coins" was extremely informative. Thank you.

 

On 12/16/2022 at 10:40 AM, Sandon said:

   The term "cleaning" is confusing because the removal of surface dirt or other foreign matter from a coin without abrasively or chemically altering the surface of the coin--cleaning in a literal sense-- isn't considered improper "cleaning" but is instead referred to as "conservation". However, both of the examples you have given would be considered improper "cleaning" and would devalue the coin. Wiping a coin, even with something soft, leaves fine scratches on the coin known as "hairlines" that are undesirable. It constitutes abrasive "cleaning" if the hairlines are sufficiently extensive or noticeable. (If a coin is wet, pat--don't rub--it dry.)  Metal polish chemically alters the surface of the coin, leaving a very unnatural appearance, and the application of the polish is abrasive as well.  Collectors want original surfaces, not surfaces that are damaged or chemically contrived. 

   For a fuller explanation and a number of examples of "cleaned" coins see my custom registry set "Characteristics of Cleaned Coins" at Characteristics of "Cleaned" Coins - Custom Set (collectors-society.com) (right click link for menu to open).

 

[Mr.Bill347]

In order to further explain what happens in the following three examples, the first coin is cleaned but hard to spot, the 2nd is cleaned and easier to see, the last has not been cleaned. All three are NGC examples.