Thanks for the link Tony...

I've been through the movement a couple of times and it was only on the last reassembly that I discovered a shattered jewel.
The movement doesn't fit properly in the case it came in so perhaps there is a spacer or retainer missing. It's just one of those mushroom type Swiss brands so I'm not really inspired to fix it. If I do want to though, I can get an NOS movement from one of my favourite selllers; they come up often

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