Do you have more information about the photo, age, origins?
Could this be a recreation of the famous tiara. If you look there are a couple of other discrepancies, the cushion shaped diamond supporting the upright, and the frame.
I know that the Diamond Fund of the RF have used modern jewellers to manufacture replicas of pieces that were sold off.... there is one of the Ears of Wheat diadem first owned by Maria Feodorovna, wife of Paul I, sold by the Soviet in 1929. In the first instance the tiara had briolette stones, which were later, effected with pave set "grains of wheat" . (The Briolette cut means that rough/uncut stones needed have to be quite big to begin with, in order to facet the gem in the round. Though I find it difficult to believe they [the new jewellers] wouldn't have had access to some large stones, as they redesigned the central stone of the Wheat Tiara to be a huge yellow diamond, -- initially it had been a 37 ct white sapphire.)
But then again. it could be the same, with the drops changed.
Reading about the jewels that most of the ladies were lucky enough to wear, I am amazed by the versatility and adaptability of them. Most pieces it seems were fitted with hidden loops, catches and pins for using one item in many ways, adding drops, or inserting posted uprights, maybe joining two or more pieces together, or unclipping sections to make a different look, changing it to complement a dress, or owing to the formality of an occasion.
It sounds like good value to me!!