I found the following extract about a brooch given to Queen Mary by the Duke of Windsor (Edward VIII). Although the year is not specifically mentioned it was 1925 following George V's illness.
From Queen Mary. A life and intimate study by Kathleen Woodward.
http://www.public-library.uk/dailyebook/Queen%20Mary.pdf The only photograph I could find of Queen Mary relating to the departure to Italy was of the King and Queen boarding the train at Calais. I suspect that Queen Mary may still have been dressed as she was when leaving London --but??
I am not familiar with the brooch HM has on her hat. My initial reaction was that it didn't look like it had onyx but, as onyx doesn't have to be black, it might. What do others think? Or does anyone know of a brooch Queen Mary wore which did contain onyx?
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