I have a little display of war nickels on my wall. Maybe Been on my wall a year. I was just giving it a closer look and darned if the coins don't appear a bit darker to me. It may be my imagination. The photos are awful, but does UV light tone coins? Before Today
As I understand it, Randy, UV radiation generates more reactive molecules of oxygen . . . a health concern, but I imagine it might very well accelerate the oxidation of metals as well.
I don't think it's doing anything as far as oxygen. Only "UV-C" light can generate ozone, and that kind of UV (a) isn't going to be present unless you're welding, using sterilization lamps, or doing some tinkering that would give me pause, and (b) wouldn't penetrate the window on the front of the display unless it's quartz (it's probably not). I don't think lower-energy UV-A or UV-B is likely to do much to coin surfaces, but it can cause other materials in the display to degrade, and some of those degradation products might be gases that can affect coins. It may also be able to yellow the slabs themselves. I don't know how sensitive modern slab materials are to UV. The labels might suffer as well.
Just sat down and looked at this. I may have misspoke. Fluorescent lights are not necessarily UV lights are they?
I wouldn’t think so but I don’t really know. It’s not like I shine my black light on them. I do shine it on yellow and green antique glass. If it lights up it’s called Vaseline Glass. I price it accordingly and into the antique shop it goes. I sell them fairly quickly.
No, they might produce a little, and the blue/purple light they produce can also degrade things over time, but you won't get a tan from them. (Unless they're the special kind.)
Randy, I'd suggest shelling out a tiny sum to increase the protection in your display. The cost of Tru Vue Museum Glass* is minimal for the sizes you'd need for that display, and the UV protection would be worth the expense...IMO. * Tru Vue is the brand name of the specific Museum Glass I'm recommending. Disclaimer: I have zero, absolutely no connection to Tru Vue or Museum Glass. I benefit in no way whatsoever if you use it or not. I have used it on framed art and the anti-reflective, no glare appearance, makes you question whether there is even glass in the frame.
Good call. I have some old rock star autographs and such that I display behind that glass. And I know right where to go get it. Thanks!
It's always the moisture. The reality is that your conditions may or never tone a coin. When you sell it, it's always the condition change that promotes a change in the coin. Many gain a skin.
Randy, when it comes to toning, the cases you have those coins in are as big of a problem, if not bigger, than anything else. They're wood, and all wood causes coins to tone. I don't know what the inserts that hold the coins are made of but they could easily be a problem too. I know display cases are popular, always have been, and lots of companies make and sell them. And lots of people buy them ! But - they are almost always a problem for coins. Especially when it comes to unwanted or unsightly toning.
Would heat cause the materials (wood & plastic) to react in a way that would/could cause coin toning as well?
Oh, yes. In general, heat accelerates any chemical reaction. With wood and paper, and some plastics, it frees up the things that do tone coins - mostly vapors containing acid and/or sulfur compounds. And, as @Pickin and Grinin said, moisture. It's possible for coins to tone or corrode without it, but it's much harder when the air is dry, and much easier when the air is humid. And if the air is humid, then everything cools off, and moisture condenses on the coin - well, then you're in a world of hurt.
