Today I found another photo of Queen Elizabeth the Queen Mother wearing the Teck crescents and roses tiara. It was published in the press in 1939, and while it mentions that the lady curtsying to her was Lady Bessborough, wife of the former Governor-General of Canada, I think that this photo was taken in London at the Guildhall in late March or early April 1939.



There is nothing in the press report where this photo was published to show when the photo was taken and so my thinking is based on the Queen's gown. It seems to me that it is the same as in the photos from the Guildhall occasion in 1939.

QEQM at the Guildhall in 1939.



If it is not the same occasion then the Queen is wearing the same gown -- another of those which were not memorable for great style.

Edit: Other photos from the same evening at the Guildhall