What was the exact origins of this particular tiara? It was mentioned in Hans Nadelhoffer's book
on Cartier that the Grand Duchess Vladimir commissioned a grand sapphire kokoshnik from them.
Did this particular tiara get purchased by Queen Marie via her sister Ducky?

Or, as Princess Ileana remembered it in her autobiography, the sapphire tiara had firstly belonged
to her Russian great-grandmother, coming through her mother via Grand Duchess Marie Alexandrovna?

Who is correct here?

So Queen Marie did buy GD Vladimir's copy from her sister?