So, I have been going through some of my random world coins to look for anything that I can use as a hole filler for my German collection until I find something better. I have a small handful of circulated Pfennig's from the West German years and a few Euro coins as well...nothing too exciting but they will fill the hole for the time being. I also have this. It's a 1907-A 10 Pfennig and although not really worth anything, it's a type that I don't have another example of. So, for now I'm going to hang on to it. I know these are a Copper-Nickel alloy (exactly what mixture I do not know)...but I'm not sure if they are prone to any specific kind or corrosion. This coin has a greenish material in and around the devices. Is this some kind of corrosion (possibly verdigris due to the copper content...if that's possible) or is it simply just "gunk" of some kind. I first thought the letters in "REICH" were corroded but upon closer inspection that looks like a severe hit in hand. Again, not that it's worth anything...more just curious.
Put it in acetone a little bit? Could be PVC residue from the past that is just now rearing its ugly head.
OK...that makes sense. Is this a coin even worth saving (or attempting to save)? It's a common date in low grade. I'm almost hesitant to put it in my German collection as a hole filler simply because it's below the quality that I'm looking for and I don't want to compromise like that.
For the small amount of effort it would take to try and save the coin I would almost always says yes it is worth trying. If for no other reason it would make it much easier for you to use it in a trade or sell it outright when you look for another. As it is now, there are plenty who would just walk away.
Fair enough. It never hurts to try and I dot have a lot of experience with such things. I'll give it a shot. Guess a trip to the hardware store is in order.
Nothing beats a good acetone soak. I take copper coins as a matter of course and immerse them for a certain amount of time. When the acetone evaporates I'm always amazed at the amount of green scum left behind.
I think I may have found another with some PVC residue on it. What do you think? I see a couple spots on the obverse in and on the wreath. Also, is there any risk using acetone on this type of coin? It's that Aluminum-Bronze alloy? I have seen some references to copper containing coins and some people having concerns.
I don't know. But I know aluminum is a funny and very finicky metal so before trying it I'd research reactions of aluminum to acetone.
OK, thank you. Does that look like PVC residue to you? In hand it's sort of a greenish color. Most prominent on the base of the wreath and the right arm of the swastika. I'll do some homework on this coin before I do any treatment. It's a lovely coin otherwise and I'd rather not ruin it.
