Got this Whitman '41-74 Some of these coins have black residue as seen on this picture. Curable? I know that cleaning coins is a numismatic sin but if there is a safe way to remove them , Please let me know. PS if anyone knows how to prevent it in the future, that will also be helpful.
Not coughing (and the like) around coins is a good start, but as for removing it, I wouldn't get your hopes up.
What was initially probably spittle as BooksB4Coins mentioned, has become more deeply embedded into the surface of the coin. It will change the color from Red to an artificial bronze color to try to get it off. Better to replace the coins and not have anyone talk/eat/sneeze over them.
Thx. What I find interesting is that it is an old one with plastic over it. So does that mean any bodily fluids marks was on the coin previous to its placement in the album?
One can only speculate, especially if talking about a Dansco-type album where the plastic covers can slide out of the way, but is a likely scenario.
Take no offense, Mike. I'm sure Finn didn't intend it as any sort of insult, but only as food for thought. Here.... please allow me to rephrase: an ounce of prevention is worth a pound of cure. By this I mean that it's less important to know the exact cause of something, and more important to avoid anything that has even the remotest possibility of causing harm. Copper in particular is a very reactive metal, so even what may seem innocuous can often be damaging.
No it isn't. Coins are cleaned all the time, every day, by lots of folks. Even the TPGs clean coins every day. If you own any older coins, it is a near certainty that almost all of them have been cleaned at some in the life of the coin. The thing that is a numismatic sin is harshly cleaning coins. As already mentioned, it is a definite possibility. Coughing, sneezing, and talking around coins quite often results in tiny droplets of saliva getting on the coins. Droplets so small that you cannot even see them. Even normal breathing through the mouth can sometimes do it. And when they do, spots, similar to those on the coin you pictured are the result, typically quite some time later. I fully realize that pretty much any dark colored spot on a coin is commonly referred to as a carbon spot. The term carbon spot has become a colloquialism, one that is used far too often and incorrectly so. The spots on this particular coin are not carbon spots. Real carbon spots are actual tiny pieces of carbon impurities in the metal alloy. And they have a far different look than spots like these. You are correct, carbon spots are not preventable. Nor can they be removed. But spots like the ones on this coin are preventable if care is taken, and they can be safely removed. There is a huge caveat that goes along with removing them however. When the dark colored spots are removed, the majority of the time they leave a light colored spot in their place. Net result, you still have spots on the coin, only of a different color. That said, those who are good enough with their removal technique can sometimes feather out the edges of the light colored spots so that they are not as noticeable as they would be otherwise. But they are never completely gone. Again, as already mentioned, the simplest, easiest, and most effective solution to this problem of spots, regardless of what caused them or what kind they are, is to simply sell the coin and replace it with another.
