I have seen many, many posts discouraging coin storage in basements, but if I can control temperature and humidity I think I may be ok. Most of the posts say a "moderate temperature" is best. Any idea on the range of temperatures considered moderate for coin storage? Thanks.
I would imagine that you'll get a fairly wide range of responses for this because some people will use desiccants and/or dehumidifiers to control moisture saturation. I've found that temperatures in the mid-70's, by themselves, have worked best for me over the last 30+ years. Bear in mind that all of that time was spent living in Southwest Florida where humidity is very high and the use of air conditioning almost year round is a necessity. Chris
As far as temperature for storage, I'd have to say, any temp lower than the melting point of the metal in the coins would be best.
What the exact temperature is doesn't really matter so much. It could be 50 degrees or a 100 degrees. What you want is for that temperature to remain fairly constant.
I agree with Doug, it's the temperature swings that do the damage. The more constant the temperature, the better. Why is this? Because everything must come to equilibrium eventually. A lot of it comes down to the humidity level. Water is the #1 most damaging substance to coins as it accelerates and catalyzes the corrosion process. In my opinion, it's the swings down that can effect coins the most as it increases the chances of micro-condensation forming. It also promotes gasses (air) moving in and out of a holder (container) providing fresh "feed materials" for corrosion.
Thanks a lot guys, this is really helpful. I have a temp and humidity device by the coins that charts these values. Once a have a year's worth of data it will tell me if that is ideal for long term storage.
Temperatures that are comfortable for people are comfortable for coins. As others have said, a low, constant humidity level and as stable a temperature as possible are best.
