The party was the second celebration of Camilla's birthday, which falls on Monday 17 July.
In the new photograph, Camilla - in a navy blue dress coat by designer Fiona Clare - poses with husband Prince Charles in the Morning Room at Clarence House, their London residence.
The Duke and Duchess of Cambridge and Prince Harry were among guests at a glamorous shindig thrown by Prince Charles at Highgrove, in Glouc.
Many of Camilla's personal friends, family members and even former staff were at the party too along with her ex-husband Andrew Parker-Bowles and her sister Annabel Elliot. Despite his many affairs during their failed first marriage, the two remain good friends.More news: Murray, Hingis Win Wimbledon Mixed Doubles
Camilla was initially blamed by some for Diana's unhappiness as she complained publicly about Camilla's continuing close relationship with Charles.
The Duchess reaches her milestone birthday in good form.
Her own image with the public has also improved from a low point after the death of Diana, Princess of Wales, in 1997.
But it's a title which has been made specifically for her.
But the survey, for the Mirror newspaper, finds more people are opposed to it than support it.More news: Bakayoko complete Chelsea deal
Do you think the public would accept a Queen Camilla, should Charles ascend the throne?
CAMILLA was a picture of youth in this 70th birthday picture by Princess Diana's favourite snapper.
The Duchess was recently filmed by ITV News cameras having a fit of giggles watching some traditional throat singing on tour in the far north of Canada.
The move will likely see her chatting to pensioners left passing their winter years with no one in their lives, who turn to the charity's helpline for a chance to have a chat.More news: Game of Thrones season 7: Sophie Turner warns Sansa will be 'unlikeable'
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