Well, well, well. I was given further gifts by Ali who said that they'd come from the same source.
I'm going to share these out eventually but all my findings need sorting so once the grandkids have gone I'll settle down to that job.
Interestingly I looked at the bag of gold rings (under and on the right of the blue bag) and initially thought they were jump rings. I never ever use those as things jump off! I always use the split rings that look like the ordinary key rings.
I got one or two out of the bag and they didn't appear to have a space where the two 'ends' of the metal meet. I've brought them home (will return them if it doesn't work) to test them with thread. If the thread doesn't wriggle it's way between the join then it'll be a 'win, win' situation. If they don't work I'll pass them onto somebody who can make use of them.