It's the top one of the three side ways sorry
Obviously, it is missing the edge reeds. You'll need to weigh it or take it to a coin dealer to see if the edge reeds were removed after the coin was made.
I don't see anything unusual. If you are asking about the green it looks like a reaction with the copper in the alloy.
Collector, occasional seller
Sorry for the delay, I appreciate the feedback, but one comment I have is it's not green, even though it appears on the photo, it's silver instead