Thank you, Knightship and Royal Watcher, for having solved the mystery.
A pity that Princess Margaretha, Mrs Ambler (if she is the one who inherited this bracelet) never wore it. I hope this bracelet will find its way back to the main branch of the Royal Family (like the Connaught Aquamarine Tiara, which was for a long time Princess Margaretha's property, before going back to the Royal family).
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