I have always been confused as to what actually was "State" and what "personal" property of the Romanovs.
Obviously coronation regalia, otherwise historical pieces & perhaps wedding jewely would be state.
But the personal? Since all Romanov wealth came from Russia itself, the monopolies, taxes, estates, all were at the disposal of the emperor. Their 'personal' allowance was in no way to be compared to the modern "civil list".
So when jewelry was commisioned for any reason, it was paid for directly from funds gained directly from the "state" of Russia, in effect at the disposal of the monarch.
Gifts from foreign entities & doweries would be a seperate category. If they were a "gift of state", well, that is self defining isn't it? I reckon most foreign orders, usually heavily jeweled would be in this category. Wedding gifts ? Who knows? I suppose that would depend on whether it was a gift from the foreign government or the personal gift of a foreign monarch.
When the Soviet gov. nationalised all personal property, no foreign country took an opposition stance, much different than say, Cuba now.
So the argument was rendered moot.
Much the same, when the exiles were selling off what they did get out, the Soviets did not put a great deal of effort to reclaim it. Unlike the post-Shah regime of Iran.
Personally, I do not care who owns what, just as long as they are available for the likes of us to see. A truely beautiful part of a fascinating history.
Cheers,
Robert