The earrings and the clips were worn to the 2002 Trooping the Colour.
I think they are the clips from the rarely seen bandeau tiara. HRH wears them on her collar and they were also worn by Lady Rose on her wedding day.
As seen on Ursula's page emeralds can be worn in the tiara as well.
This double clip brooch has also been worn. It has the same overall shape of the other clips, but the diamond motifs near the wider end is different. If these are the same, the emeralds must have their own diamond surround that is inserted into the center. It would be interesting to see a closeup of the rubies to compare.