In Colin Mahoney's book, "Masterworks the paperweights of Paul Ysart", he commented that Pauls' son, Salvador remembered Paul coming home one day with a box full of "medals" [my quotes - since I believe "medals" meant cap badges, etc.].
And Colin suggested that this indicated a "form of experimentation" rather than anything to do with the war(s) or troops in the area.
It is interesting to note that of the cap badges that have been researched I think most, if not all, were from regiments that existed before WWII - and some (or most?) of those were no longer in existence by the time of WWII. So ... perhaps a number of the cap badge (etc.) weights were encased on request from "old soldiers"? But there is proof of this one way or the other. ( * )
However, I think it is very unlikely that specific regiments made requests for badges etc. to be encased as weights.
As for the weight in this thread ... I have no idea if it was by Paul Ysart or made in Belgium / Alsace region, or somewhere else entirely!!
( * ) Edited to confirm - should have said, "But there is no proof of this one way or the other".