Hello again NumisRob. Thanks for the info. I've just had a quick look through my decimal one pennies and found a couple from 1994 (Maklouf) that may be of interest. They show the differences in the rivets on the portcullis. From 1971 to 85 they all have simple bosses, then up to 1994 both types exist, but after that they all have the incuse ring, except for 2007. I'll look into what you said about the serifs when I'm back from my busman's holiday.

