Looking at the video I think it could be her diamond sautoir divided into two strands
--Previous Message-- : I wonder if this video might help in : identifying the necklace. : : Queen Mary's jewels can be see at : approximately 2.04 minutes. I very much : doubt if QM's necklace is composed only of : pearls. I think that there are darker : gemstones at intervals and I can see flashes : of diamonds. In contrast the necklace worn : by QEQM is clearly strands of pearls. : : : : : :