I thank you so much for your kind answer !
1° First bracelet :
I also thank you because I had never seen a photo of the unknown bracelet worn in 1976. It is a sapphire bracelet I had never seen before ! Great !
Obviously, the same bracelet worn in 1983 in Vancouver is different !
Second bracelet :
I also thank you for your kind post concerning this bracelet ! It is one of my mystery ! Indeed she has worn on least once this "huge diamond bracelet" with the Granny's Chips and the Greville Chandelier earrings !
Please find a below a photo of the event (1963 ?)
However, we can't see the bracelet :
It is a different bracelet !
Last but not least I am convinced that the bracelet worn in 1983 is the bracelet with the demi-parure !
I am really perplexed by Franck's photo and am inclining to the idea that it does show the Dubai sapphire bracelet, but I would like to test a couple of other ideas.
I noticed that in Canada in 1976 the Queen wore a bracelet which is unknown to me. Perhaps some one has a better image showing the front of the bracelet.
I don't think that this is the sapphire bracelet which HM often wears with her sapphires. The two photos below show practically the entire bracelet which HM normally wears.
The second is a bracelet which the Queen wore at the Louvre in April 1957. I cannot confidently identify this bracelet, although I think it might be the Chain Link bracelet. If it is, then this is definitely not the bracelet HM wore in Vancouver with the Dubai sapphire necklace.