OK..... I'm probably going to get flamed off the forum for this, but does anyone have detailed advice on cleaning gold coins without doing harm? Passive soak in soapy water? Ultrasonic cleaning? What can I do?
As the doctor's oath says: First, do no harm. Think about cleaning, and then put it out of your mind.
Not PVC damage.... mostly just dirt particles. I do not want to gain luster or anything like that. I just think that dirt/ grime is especially unatractive on gold. I do not want to rub, shine, polish, or do anything detrimental. Just get rid if the dirt, grime, et cetera. I know "cleaning" can be detrimental but there has to be certain approved methods since the TPG's used to dip coins for people. Maybe they still do.
I alwyas hear people talking about how dipping coins will get you in a body bag, but if you read carefully into the standards having a "improperly dipped" coin will get you in a body bag, but having a "dipped coin" will not. What gets people with dipped coins is returned in a body bag is dip residue. Washing the coin off with a nuetral solution is reccomended after dipping to avoid this. Also, you constantly here people talk about how "dipping" coins removes metal from the coin's surface. While this is true, it took an exremely powerful microscope, and a coin that had been dipped over and over again to prove this. Usually dipping coins in reccomended solutions only removes the patina, and if any metal is removed it is extremely limited, and usually cannot be detected. On the other hand dipping may be obvious for a number of other reasons than actual damage being done to the coin. Just because a coin looks worse does not mean it has been damaged. It could be that dipping has merely exposed preexisting weaknesses. Also, dipping residue stains can be removed. Of course I really don't have experience with this, and therefore that is why I asked the question. NGC has a nograde.pdf you can download. It explains exactly what gets you a body bag.
I will give you a couple of ideas. Remember though with each of these the last step is always a distilled water rinse. The first attempt at removing the dirt might be a simple water stream to dislodge it. This could be from a waterpick or kitchen faucet spray while carefully holding the coin by its edge. Water does not harm gold so this should be safe to do unless you use too powerful of a spray. Rinse with distilled water. If that doesn't work then a soak and spray might be the next step. The hard part is finding a way to soak without having the coin touch a surface. You can hold the coin in water if you have the time, if it is a very valuable coin I would be careful doing this. Maybe place it inside one of the coin flips and fill with water. Then try to spray it away after a soak and risnse with distilled water. The last somewhat safe attempt is acetone but it will not remove general dirt, only oil or plastic types of contamination. Also it is dangerous to use and often contaminated itself so never allow it to dry on the coin. Rinse in distilled water right after exposing to acetone and use at least two rinses in different cointainers, the more the better. You did mention soapy water and I have never tried that as I would be afraid that some soap residue would remain after even a couple of rinses and would dry on the coin. The last thing you want is for the coin to be worse off that you started. Anyway these are only suggestions and should be done carefully if attempted. Also I would call these attempts more at coin conservation and not cleaning as you are simply trying to bring the coin to its original surface and not remove anything to alter the coin. If anyone disagrees though feel free the critique this but I have used these techniques and think they are safe if done carefully [and especially using acetone only outside of a house or building].
Well don't try it on that coin. If you wish to experiment fine, but do it with pocket change until you learn what you are doing. More coins have been ruined by beginners trying to clean them than any other cause you can imagine. Why ? Because just like you they always think that somehow they can make the coin look better. Well guess what - 99 out of a 100 times you can't make the coin look better. Your best bet is to leave it alone. The only time that you should attempt to clean a coin is when it is necessary to prevent further damge from a harmful substance being on the coin. Yes, coins can be safely cleaned. But that can only be done by someone who has the necessary experience and knows what they are doing. You, admittedly do not. That's your answer.
There is a special solution made just for people that want to clean Gold coins. It's called Aqua Regia. Try a chemical supply house for some. you will be amazed at how much dirt that stuff removes. :smile Please don't do that. Just do as GDJMSP says.
The really hard part about this is being able to spot a coin that can actually be helped. Very few can in my opinion. Next a person must know the proper method for that type of coin and for that type of problem. For these reasons I tell folks to leave them alone unless it's something easy to deal with like PVC.
Cleaning vs. Consevation Isn't there an accepted difference in the hobby? Cleaning Seems to have an obvious negative conotation associated with it in the world of coin collecting, and rightfully so as usually it involves changing the "metal surface" of the coins. Conservation however seems to be viewed as a positive action in some circles. I definately do not want to ruin anything, or alter any surfaces. Removing small dirt deposits is more what I am looking for. I will take take the advice of the masses as I do not want to destroy anything, but if someone does have good advice on conservation I would appreciate it.
You can purchase a product called MS 70 that should break up the dirt. You use it like a dip by pouring it over the coin is a small bowl. Rinse the coin extremely well after and do not run the coin with anything. MS 70 is accepted by NGC as well as PCGS as I have used it on a few coins then had them slabbed.
