I am beginning to lean toward the notion that the brooch contained rubies, but I stress that it is not a definite conclusion.

Why possibly rubies?

During the visit to the Emperor of Japan, Princess Alexandra was photographed without her gloves, allowing us to see 2 bracelets.



Detail of bracelets


During the same overseas trip on her visit to Myanmar (Burma as it was then called) Princess Alexandra was presented with a suite of ruby jewellery some of which she immediately donned.





The bracelet Princess Alexandra wore on her left wrist is the same as one she wore in Japan.

Detail of bracelet worn in Myanmar.



Comparison


Although the Burmese gift was said to include a bracelet, this bracelet had been part of the Princess' existing collection. According to Alamy images the photo below (where it can be seen on the Princess' left arm) was taken circa 1956.



Because of the appearance of this bracelet in the photos of Princess Alexandra wearing the Burmese gift, I am inclined to think that the bracelet contains rubies and, if Princess Alexandra wore matching gemstones with Princess Nicholas' brooch, then it contained rubies.

But did it? We know that Princess Alexandra frequently wore a necklace containing multiple coloured gemstones during this period -- as for example



so I am still keeping an open mind

I wonder what happened to this brooch?

PS I wonder if others noticed that in the photos taken in Myanmar (Burma) Princess Alexandra was wearing thongs? I suspect that this is the only occasion on which a royal has been photographed wearing thongs for an official engagement. How many hours of angst took place before the British officials agreed that the Princess would wear thongs?

[I know a cultural translation is necessary!! Thongs is the term used in Australia and Asia for what others call flip flops.]