In
Tiaras. A history of splendour Geoffrey Munn page 119 notes that the photo he has of the elaborate Curzon diamond necklace was of a necklace ordered from Boucheron on 14 February 1905. Munn also notes that the necklace appears to have been altered. As Munn details the number of diamonds used and the total carat weight, it seems that this information has been taken from Boucheron's archives.
The date of 1905 is perplexing, as Lady Curzon was photographed wearing the elaborate diamond necklace in January 1903.
1903 photo
What to make of all this?