Thank you for the photos of the Queen and the Princesses, Arthur.
What superb views the photos give us of the Queen's tiara elements.
These photos show the design of the necklace clearly. I suspect, that being able to see these jewels in person would provide an entirely different impression from a still photo.
I'll continue the debate by saying that I rather like the necklace.
As the Prince Consort has given HM a number of striking turquoise jewels, it would appear that both of them like this gemstone.