Hi everyone, I handle my ancient coins quite often( after washing my hands or disinfecting them of course) And recently I have noticed the edge of my coin has slowly turned darker and darker.( I only handle my coins by the edges) This got me really stumped and I have no idea what could be causing this...any help would be appreciated..
I know that some hand washing soaps such as SoftSoap have what would be considered a small amount of alcohol in them. While it may be small for us, there is a the possibility of trace amounts combining with body oils and getting on the coin edge. Not saying this is whats happening, but it is the only thing I can think of at the moment.
Sulfur can darken coins. I remember when I was a kid and used a Whitman folder for my Roosevelt dime collection. After a few year, the edges of the (pre-1964) coins all starting turning dark. Not sure why you'd have sulfur on your fingers, though. Your name isn't Beelzebub, is it?
It could be that the coin was treated for horn silver, but incompletely. In my experience, after a while these coins become darker, usually starting at the edges. I would need to see detailed pictures of the entire coin to give an opinion though.
I see no evidence of prior horn silver. Silver does react with sulphur, as mentioned above, which can be present on your fingers.
Thanks everyone for your help, judging from all the answers, it might be because of my pocket hand sanitizer that I use quite often....it contains alcohol and I being dimwit rubbed it all over my coins... I have heard lemon juice can remove the tarnish, but can anyone please let me know the best way to remove the tarnish without damaging the coin?
The purity of the silver in these tetradrachms is pretty high. Lemon juice should not damage that coin.
I would leave it alone. Restoration of silver coins is difficult and you might end up with a shiny silver coin (which is undesired). Silver naturally tarnishes.
I would just leave it as it is. I've come to enjoy the different toning of my silver coins, and I enjoy watching them change over time in my display cabinet.