Thank you, Alyend. I do not know what Queen Victoria is wearing under her Baden Fringe Tiara. I would incline for a veil, but I am not really sure.
I think that Grand-Duchess Louise of Baden is wearing the heart-shaped palmette diamond tiara, which is now in Queen Margrethe II of Denmark's collection (through Queen Victoria of Sweden, King Gustaf VI Adolf of Sweden and Queen Ingrid of Denmark):
(Credit: Chris Jackson/Getty Images Europe, via Zimbio.com)