Need some advice on cleaning some coins

Alas...the difference between CONSERVATION and CLEANING. Exactly why, regardless of Doug, we should use the proper terminology with coins. I don't think NCS would get much business if their name was "Numismatic Cleaning Service".

 

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MY chops get busted for not using "proper terminology" when taking a humorous swipe at someone who uses "you should might as well" in a font the size of a small planet?

Thank you so very much, syntax master. :too-funny:

 

I was not aware that metals had the ability to absorb water, and this thread makes me thirsty.

 

Many good folk at CT have provided their good opinions. I would like to see photos of the OP's coins.

A pure Acetone rinse & air dry before storage might be good advice for some Silver & Nickel coins but I want to know more about the coins first.

 

It's not so much that it will absorb water in the way a sponge will, it's more that metal can coordinate with water molecules on its surface. But here's why I wouldn't worry about that -- any fresh metal will quickly form oxides all about its surface that will actually protect the metal from further oxidation and if the coin is more than a year or two old, then the surface metal has been coated (if you will) with a complex of surface oxides. Like the example of rust on iron, if you leave the rust on the surface it will protect the metal beneath it from further oxidation and the only time you would want to remove the rust is when you're going to paint that now fresh surface. And coins will do something very similar after being introduced to air. Acetone will not remove this oxide layers on a coin since acetone is primarily an organic solvent and removes organics only. So as I mentioned earlier, I do not believe there is anything to worry about when using water on a coin that has been exposed to air for many years. However, this would not apply to a coin that has been "dipped" and the surface oxides have been removed.

 

Your skull is just too thick. :yes:

 

Google "adsorbtion".....exactly as I spelled it.

 

Sorry to butt in, but reading this leaves me with a couple questions. Maybe they're helpful to more newbies than just me?

1. If a silver coin was improperly cleaned (not by me), what do you speculate was done to it? See pic below. If I cracked it out of the holder and waited however long, it would probably never tone normally again, correct? Might as well leave it as is?



2. If a gold coin was improperly cleaned (again, not by me), same question. Except the toning part. What exactly would happen to the gold if it were cracked out of the slab? Pic below...



I'm guessing that with the silver coin, the improper cleaning was obvious to the grading company due to the black toning and the streak. But with the gold one, what's so obvious? Is it residue on the coin? The softened details? Any chance of regrading the gold coin?

 

LOL I think I am learning alot but at the same time damn I feel stupid lol. Just for the record I got a bunch of Lincoln cents from a friend that had them in an ashtray. They all looked like grabage but they had rainbow toning on them and I thought to myself well why not try to clean them and this might help with my anger problems (I am a Soldier and therefore I have alot of those lol). Of course these cents are for no one but me and they wouldnt be sold to anyone cause lets face it they are Lincoln cents that no one would want. So I read a few posts on conserving coins not cleaning and well I went to the local hardwear store and bought a big can of acetone. I have dipped them and rinced them and now have a lovely collection of rainbow toned Lincoln cents that belong all to me (I will post pictures soon on a new thread so keep an eye out). Long story short if you want to clean your coin or in better terms conserve your coins they are your coins and you should do what you want with them. Dont let others tell you what to do with YOUR HOBBY. If you plan to sell those coins well ask for advise, do some research and talk to some of the people here at CT. They may not always see eye to eye as you can see from this thread but they obveously have certain points that each can be validated. I have been trying to learn how to do this for quite some time and with the help of one of the members here in CT I am learning alot about many things to do with coins. By the way thanks BadThad for the help you have given me I deffinatly have learned alot. If you dont like what I have to say well that is your opinion dont belittle me over it because I am not going to change over the fact that you think I am wrong lol. I am learning alot from all of you though lol have a great day.

 

Back in the 1950's there was a notion that no one should have dull or grimy coins and that cleaning them didn't matter. Some coin mag's even had articles about how to do this, often time rubbing them with baking soda and water. King Farouk was a big time believer in this and ALL of his coin were cleaned this way. As you can probably guess, a scouring agent like baking soda will leave hundreds of small hairlines where the metal was gouged. Most likely this was when the coins were cleaned. However, there's a coin shop near me called The Treasure Trove" and has been in business for 48 yrs and he STILL does this to nearly every raw coin that comes thru his shop. One day he actually showed me how I should "clean" them so I know this first hand and not thru hearsay. As I watched him wet the coin and put it in the big bucket of baking soda I could feel the blood drain from my head as he was rubbing the coin between his thumb and fingers and all I could say was that I didn't think that was a good idea. He replied that it was fine and that he's been doing it for years. Oy veh...!!!

 

Me chemist too, Me splain, Absorption - taking water into the interior like a sponge. Adsorption - forming a surface layer of something through an attraction. Yes, everything in air containing moisture will adsorb some moisture. Now for my conjecture. Coins have a convoluted surface and excess moisture has a chance of collecting in the nooks and crannies. This moisture might not evaporate as rapidly and could possibly cause corrosion/toning/discolloration. Unlikely with gold, more likely but not really too bad with silver, copper has the most chance, not to mention aluminum. The acetone rinse would leavethe surface pristine and let it be hydrated naturally.

 

Everything eventually comes to equalibrium with it's surroundings....that's nature. However, the speed at which that happens and perhaps the thickness of the layer over time can be GREATLY minimized with proper storage technique. Isn't that the point of coin storage? Why would you rush to saturate/hydrate a coin surface by making the mistake of using a final water rinse? If you're seeing a white haze after acetone, it's too late, the surface is already deeply oxidized. The coin should be replaced if you see that because that's the true surface. Water is simply hiding the problem much like oil covers a problem. Now, back to you.....

I dare you to deny that what I said is true!

 

Do not clean coins. Period. I grade coins and the grading is not enhanced at all

 

This is probably the reasoning the old time collectors came up with varnishing coins to protect them.

 

I don't have much doubt you're right. Water will get down in between the atomic lattice of the metal and can take significant energy to dislodge. But even water from the air can get lodged down in here and if the air is dry enough or the surface warm enough nothing will keep the water molecule from moving into the air.

I'm not sure why coins often come out of the acetone hazed and perhaps you're right that this is their "natural" state but rinsing in water will prevent this many times and I've never had trouble with coins turning once they've been properly dried. I just leave the lid of the roll loose for 24 hours so water has a chance to stabilize with the air. So long as humidity is low I'd be surprised to see any problems.

I guess what I'm saying is that if a method works it just doesn't matter why it works.

Now, if I could just find a way to get the dang olive oil out of that lattice.