In the past I have referred to it as the tuning fork tiara.
Edit: attempt at humour. I try to avoid that label now.
--Previous Message-- : Thank you for the side by side photos Nellie. : : This is the tiara I was alluding to. : : Apart from the metal under-structure in the : middle of the tiara, I think it suits the : Countess. : : In the photos we have seen of QEII with the : tiara, the upright metal pieces in the : middle of the tiara are hidden. : : Unfortunately, the Countess' hairstyle does : not disguise that element. I personally : would like to see that metal section : disguised. : :