Cleaning/preservation question
MrBear
Posts: 379 ✭✭✭
Hi All!
Back in 1876 for the Centennial, my synagogue buried a time capsule that included around 50 coins (silver & copper or bronze). It was dug up in 1976 and cleaned off, and at some point after that (80s or 90s maybe) the coins were arranged and mounted (with some kind of adhesive) behind glass in a frame that hangs on the wall in our museum. I have no idea whether they were cleaned off with mild soap and water, or whether harsher treatments were used. A few of the bronze coins are quite green, and a half dollar looks uncirculated except for a smattering of green staining (again, probably from another coin) on it.
So here's my question...it's been suggested that the coins should be professionally treated to prevent further degradation, so is that worthwhile? My non-expert assumption is that the coins are stable, given that they spent a century buried and are now clean and dry and in a relatively climate controlled environment. And that after decades glued to a piece of cardboard, things aren't going to be any worse.
Comments
They've only been in the current environment for 40 years. In addition, the current environment has air and moisture in it. There is no reason to believe that they are stable.