Looking for confirmation that the reverse's center blob is probably ex-jewelry and not a cud. Thanks for the input.
Don't know exactly what that is, but it is not a cud. A cud involves a rim to rim raised area. It could be a die break, or as you said a jewelry piece. Is the blob as hard as the other metal? If silver solder was used it could be the same hardness (or close to it). if common lead solder was used the blob will be much softer than the surrounding metal.
Definitely not a cud as cuds must touch the rim. Not sure what it’s from. It may be from a jewelry piece such as a pin or a broach.
Usually with jewelry there is a loop or a removed loop at 12 o'clock. Assuming this is solder, and held it in place in a ring? You could very gently warm it and remove it since it has a lower melting point. If it wasn't a rare date. Perhaps there is a solvent that could remove it but again there is the risk of disaster. Too bad on this key/semi key date.
My impression is that it's solder from when it was used for a button or attached to a pin or clasp. The black stuff has the appearance to me of plating or painting that has chipped off but not sure, maybe it's something else.
