Thirties Omega ladies jewellery watch, all info appreciated.

I wonder if any of my experienced fellow ΩF friends ever came across a watch like this? AJTT was of no help.
It is extremely small, probably about 15 mm wide. The case is platin.
When the watchmaker opens it, I will post a movement photo.
I fear that the movement is shot, and we shall see if it is possible to source a replacement.

Someone might put me straight if I’m wrong, but I think the style of the Omega would be called art nouveau, a style trend that was prominent 100 years ago. The platin refers of course to platinum, a medium quite suited to complex styles such as jewellery with many stones. The calibre cut sapphires are trapezoidal in shape, and bezel set. The larger diamonds appear to me to be round brilliant cut. As to finding a replacement movement? I’ll go out n a limb and say there’s no chance. Don’t give up the notion of having the one in the watch repaired. The primary purpose for the design of this watch is as a jewellery item, and not as a practical daily driver. Cases such as this one tend to leak dust, dirt, and moisture as a result of all the holes that were drilled to accommodate the diamonds. Further opinions might be better sought from a gemologist in light of the composition.

Thanks a lot, @OMTOM ! I spent half an hour with AJTT without finding these gems. Embarrassing.

She would most certainly wear it even if non-functional, but it would be nice if it worked.
Watchmaker just opened it and confirms that it is indeed a cal. 12,3F, and with broken balance. But he is not ready to give up, he says, which sounds comforting.