That picture still has me enveloped, and it's just because if it's a made up picture the person who did it must be very very good. The person has been able to place the necklace QM received as I think a wedding gift among all those other ropes of pearls and I believe diamond necklaces. It looks official and it's not that hard to imagine QM adorned like that knowing the character she was with a penchant for all things jewels.
Regards,
Dave.

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I think that is an amazing mock up, a composition of Queen Mary's head,some of Queen Alexandra's jewels and some of Queen Mary's.
There are genuine official portraits of Queen Mary.
I post a few in a few minutes.