I knew I left that somewhere...Someone in my neck of the woods seems to have found one. Unfortunately it wasn't me. https://www.coinworld.com/news/us-coins/2018/10/collector-finds-1983-bronze-cent-in-circulation.html
It says multiple examples have come from Philly but only 1 1983-D. But there are a couple other Denver coppers, 1989-D and another (I forget the date early 90's?) Doing quick net searches, I don't find the other Philly off metal transitionals. At the end of the article: The results determined the coin is 93.3556 percent copper, .009 percent silver, 6.5138 zinc, 0.0434 percent nickel and 0.772 percent iron. The standard composition should have been 95 percent copper and 5 percent zinc. How does the trace of silver get in the alloy?
Most newly mined silver today comes as a byproduct of copper mining. it is removed as a contaminant of the copper. Well you can't get it ALL out so a trace of silver is left behind in the copper. .009 percent is 90 parts per million.
I do not like the chemical ratio either. If they can counterfeit cents so well in China, why not the metal. Silver I can understand, Ni and Fe ?? I'll pass.
