In 1919, the Allied powers unwisely decided to reshape the map of Europe, this would lead to the next War in 1939-45. The Austro-Hungarian Empire was carved up and "new" Countries where created such as Czechoslovakia/ Yugoslavia/ other parts went Boleshivik Russia. Serbia which had ignited the First War, by the assasination of the Archduke Ferdinand in Sarejevo was master of the new Yugoslavia. In 1941 when Yugoslavia surrendered to Germany, many of the old ethnic groups joined up with the Axis/ Allied Powers. Even among the Serbs/ the Chetniks fought on the German side, same for the Bosnian Muslims/ Croats. My coin is from the new Country of Croatia AV 500 Kuna 1941 Zagreb Mint Ante Pavelic
Trying to think back to my chemistry days. When we had reactive metal reagents which were air or water sensitive, they were often stored immersed in an inert oil. Or you could try to encapsulate it in an atmosphere of nitrogen or argon. Not too many things can be counted on to stay airtight over many years, though.
Had you seen this thread? Sounds like zinc oxide can be dissolved with dilute acid (and then rinsed!), but it would tend to leave pitting behind. Once the metal has oxidized there's only so much you can do. Sorry I don't have any better advice.
Thanks, I hadn't seen that. All I want to do is try and prevent further reaction and preserve what's left. I've got much worse zinc than this one.
