It could be a new piece. It does look like an Art Deco Design, could it have been a piece bequeathed to QEQM from Mrs. Greville? Eugenie's wedding tiara sat for many years before seeing the light of day and it was a Greville piece. What ever the origin, it's a stunning brooch.
A new purchase given as a Christmas present, I suppose?
It certainly looks to be a rather large diamond in the middle - dazzling.
This is the best I could do with it.
It does seem to be all diamond where I had previously thought there might be a pearl centre.
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