My wife bought me a tie clip last July for my birthday. It was in Gem BU when I got it. I did photograph it 10 months ago. I have kept it stored in the white cardboard box it came in. And when I opened the box today, much to my surprise this is what it looked like. This seems like a very short time for this much toning to accrue. It has change some of my ideas about the whole toning issue. Some Dip on a Q-tip brought it back.
It was probably treated with something before it was mounted on the tie bar. The "something" was not properly removed, and the piece toned quickly. If nothing was touching it in the box, that's the only logical explaination.
That is a pretty dramatic short term change. I would bet @johnmilton is correct...... I only wear a tie Sunday’s at church. But now I gotta find me a coin tie clip. That’s pretty cool.
Normal technique is to use silver solder which uses a flux, which then has to be cleaned off. The term flux remover can be used, but it is usually an acidic solution close to EZest type, The term old timers use is "Pickle" . They are usually stronger than the coin stuff. but the jeweler when done can coat it with a film so it doesn't corrode ( err, tone) as fast. Jim
When the coin is in the box it almost touches the top cover of the box. It could be chemicals from the paper box. I do not think that solder was used to secure the coin. It looks to be pressed into a bezel using the reeding to keep the coin in place. I say this also because you can order the tie clip with different year coin of your choosing. Which would help to fill orders rapidly. Don't even need to be a Jeweler to do that. But I can not say for sure that it does not have solder. It is going back in the box, I have no idea for how long. I'll put a couple of BU dimes in the bottom of the box, just out of curiosity. Maybe I can remember to check it once in a while.
It doesn't need to touch anything, contact with other materials is not what causes the toning. It's the gasses put off by the other materials that cause the toning ! And since cardboard contains high amounts of sulfur - that's the explanation for the toning. As for the rapidity of the toning, that's rather easily explained as well. Given the lack of any toning at all to begin with, the coin was obviously dipped or cleaned with an acidic solution of one kind or another. That results in fresh silver being exposed. And then the coin is trapped inside a small closed box which is full of sulfurous gasses. So it's only natural for it to tone like that, and that fast.
