The release of three pictures of Kate, shot by fashion photographer Paolo Roversi at Kew Gardens for the milestone, has been dubbed "a fascinating departure from the images we've grown accustomed to seeing of her".
Writing in The Telegraph, author Lisa Armstrong said Kate, showing "grandeur and modernity" seems now "finally unafraid to be a fashion template".
The three images, which see her wearing three different Alexander McQueen gowns, were praised by Ms Armstrong to the point of comparison with the portraits of the Queen taken by Cecil Beaton in the 1930s.
She said: "The picture of a seated Kate could hang side by side in the National Portrait Gallery with Beaton's 1939 portrait of Queen Elizabeth as a reassuring demonstration of the British monarchy's continuity and its ability to heal itself after family rifts."
The images of the Duchess will in fact be included in the permanent collection of the National Portrait Gallery, of which she is Patron.
Mr Roversi, who has photographed top models of the likes of Naomi Campbell and Kate Moss, described working with Kate as "a true honour" and "a moment of pure joy" and said with her "positive energy" she can "bring hope to the whole world".
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