There were numerous excellent guesses on the small thimble, but the only correct guess was from Yvonne who said it looks like a Monopoly game piece. Yes, that's it, and I thank you all!
While the Monopoly piece in the shape of an iron has been retired, the thimble has not, so there are new shiny ones out there. However, this one is vintage, so Carol, I suspect the greenish hue is some kind of patina.
Yvonne, watch your mail although I'm not sure what I'll send yet. More NJ sea glass perhaps? ;)))