Beth wrote a very interesting post about Jean Templeton Ward's diamond tiara in last November.

Janet recollected that a very similar tiara was auctioned at Drouot Paris in 2018. The catalogue on page 36 suggested a Russian aristocratic provenance.

The tiara which sold for 582 000 Euro is now advertised by FD Gallery in New York City as »A Diamond Clover Tiara, by Cartier. The openwork tapering tiara, millegrain set throughout with diamonds, with a clover motif at the center with a large European-cut diamonds, total weighing approximately 41.00 carats, made in 1910.«

On Instagram FD Gallery just published the following additional information:

»Previously in the collection of Jean Templeton Ward, formerly Jean Templeton Reid. Jean was the only daughter of Whitelaw Reid, the American Ambassador to the Court of St. James. She lived in London after her marriage to Sir John Hubert Ward, the son of William Ward, Earl of Dudley. They were married in 1908 at the Chapel Royal, St. James Palace in a ceremony attended by King Edward VII and Queen Alexandra, and was considered one of the greatest society events of that year. ⠀
The tiara is pictured being worn here by Jean's daughter in law, Margaret Susan Corbett, in 1950. Margaret had married Jean's son John Ward in 1934.«

Neither their website nor their Instagram post mentions a possible Russian provenance.